U.S. patent application number 15/081503 was filed with the patent office on 2016-07-21 for heat-resistant silane crosslinked resin molded body and method of producing the same, heat-resistant silane crosslinkable resin composition and method of producing the same, silane master batch, and heat-resistant product using heat-resistant silane crosslinked resin molded body.
This patent application is currently assigned to FURUKAWA ELECTRIC CO., LTD.. The applicant listed for this patent is FURUKAWA ELECTRIC CO., LTD.. Invention is credited to Arifumi MATSUMURA, Masaki NISHIGUCHI.
Application Number | 20160211050 15/081503 |
Document ID | / |
Family ID | 52743602 |
Filed Date | 2016-07-21 |
United States Patent
Application |
20160211050 |
Kind Code |
A1 |
MATSUMURA; Arifumi ; et
al. |
July 21, 2016 |
HEAT-RESISTANT SILANE CROSSLINKED RESIN MOLDED BODY AND METHOD OF
PRODUCING THE SAME, HEAT-RESISTANT SILANE CROSSLINKABLE RESIN
COMPOSITION AND METHOD OF PRODUCING THE SAME, SILANE MASTER BATCH,
AND HEAT-RESISTANT PRODUCT USING HEAT-RESISTANT SILANE CROSSLINKED
RESIN MOLDED BODY
Abstract
A method comprising at least a step of preparing a silane master
batch by melt-kneading a base resin (R.sub.B) containing a
non-aromatic organic oil, an organic peroxide, an inorganic filler,
and a silane coupling agent, in specific mass ratio, and a step of
mixing the silane master batch and a silanol condensation catalyst
or a silane master batch; a heat-resistant silane crosslinked resin
molded body and a heat-resistant silane crosslinkable resin
composition prepared by the method, and a silane master batch and a
heat-resistant product.
Inventors: |
MATSUMURA; Arifumi; (Tokyo,
JP) ; NISHIGUCHI; Masaki; (Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
FURUKAWA ELECTRIC CO., LTD. |
Tokyo |
|
JP |
|
|
Assignee: |
FURUKAWA ELECTRIC CO., LTD.
Tokyo
JP
|
Family ID: |
52743602 |
Appl. No.: |
15/081503 |
Filed: |
March 25, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
PCT/JP2014/075752 |
Sep 26, 2014 |
|
|
|
15081503 |
|
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01B 3/28 20130101; C08J
2325/08 20130101; C08L 23/0815 20130101; H01B 3/22 20130101; H01B
3/441 20130101; C08J 3/226 20130101; C08K 5/14 20130101; C08J
2325/04 20130101; C08J 3/24 20130101; H01B 7/292 20130101; C08L
23/06 20130101; C08L 23/0815 20130101; C08K 5/14 20130101; C08K
5/54 20130101; C08L 23/06 20130101; C08J 2423/16 20130101; C09K
21/14 20130101; C08L 23/06 20130101; C08K 5/54 20130101; C08K
5/5425 20130101; C08L 91/00 20130101; C08L 23/0815 20130101; H01B
3/442 20130101; C08J 2323/08 20130101; C08J 3/22 20130101; C08K
5/54 20130101; C08L 91/00 20130101; C08K 5/54 20130101; C08K 5/14
20130101; C08L 91/00 20130101; C08L 91/00 20130101; C08K 5/54
20130101; C08K 5/54 20130101; C08K 5/14 20130101; C08L 2207/322
20130101 |
International
Class: |
H01B 3/44 20060101
H01B003/44; C08K 5/5425 20060101 C08K005/5425; C08J 3/24 20060101
C08J003/24; H01B 7/29 20060101 H01B007/29; C09K 21/14 20060101
C09K021/14; C08J 3/22 20060101 C08J003/22 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 27, 2013 |
JP |
2013-202670 |
Claims
1. A method of producing a heat-resistant silane crosslinked resin
molded body, comprising: (a) a step of obtaining a mixture by
melt-mixing, to 100 parts by mass of a base resin (R.sub.B)
containing a non-aromatic organic oil of from 5 to 40 mass %, an
organic peroxide of from 0.01 to 0.6 parts by mass, an inorganic
filler of from 10 to 400 parts by mass, a silane coupling agent of
from 1 to 15.0 parts by mass, and a silanol condensation catalyst,
(b) a step of obtaining a molded body by molding the mixture, and
(c) a step of obtaining a heat-resistant silane crosslinked resin
molded body by contacting the molded body with water, wherein the
step (a) has a step (1) and a step (3) below, and when part of the
base resin (R.sub.B) is melt-mixed in the step (1), the step (a)
has the step (1), a step (2), and the step (3) below: Step (1): a
step of melt-mixing all or part of the base resin (R.sub.B), the
organic peroxide, the inorganic filler, and the silane coupling
agent, at a temperature equal to or higher than the decomposition
temperature of the organic peroxide, to prepare a silane master
batch, Step (2): a step of melt-mixing a remainder of the base
resin (R.sub.B) and the silanol condensation catalyst, to prepare a
catalyst master batch, and Step (3): a step of mixing the silane
master batch and either the silanol condensation catalyst or the
catalyst master batch.
2. The method of producing a heat-resistant silane crosslinked
resin molded body according to claim 1, wherein the base resin
(R.sub.B) contains 5 to 40 mass % of a styrene-based elastomer, and
a mass ratio of the content of the non-aromatic organic oil to the
content of the styrene-based elastomer is from 1:5 to 2:1.
3. The method of producing a heat-resistant silane crosslinked
resin molded body according to claim 1, wherein the base resin
(R.sub.B) contains 5 to 40 mass % of an ethylene rubber, and a mass
ratio of the content of the non-aromatic organic oil to the content
of the ethylene rubber is from 1:5 to 1:1.
4. The method of producing a heat-resistant silane crosslinked
resin molded body according to claim 1, wherein the base resin
(R.sub.B) contains 30 to 95 mass % of a linear polyethylene having
a density in 0.92 g/cm.sup.3 or less or an ethylene-.alpha.-olefin
copolymer.
5. The method of producing a heat-resistant silane crosslinked
resin molded body according to claim 1, wherein the mixing amount
of the silane coupling agent is more than 4 parts by mass and 15
parts by mass or less, with respect to 100 parts by mass of the
base resin (R.sub.B).
6. The method of producing a heat-resistant silane crosslinked
resin molded body according to claim 1, wherein the mixing amount
of the silane coupling agent is 6 to 15.0 parts by mass, with
respect to 100 parts by mass of the base resin (R.sub.B).
7. The method of producing a heat-resistant silane crosslinked
resin molded body according to claim 1, wherein substantially no
silanol condensation catalyst is mixed in the step (1).
8. The method of producing a heat-resistant silane crosslinked
resin molded body according to claim 1, wherein the amount of the
silanol condensation catalyst is from 0.05 to 0.5 parts by mass,
with respect to 100 parts by mass of the base resin (R.sub.B).
9. A method of producing a heat-resistant silane crosslinkable
resin composition, comprising: (a) a step of obtaining a mixture by
melt-mixing, to 100 parts by mass of a base resin (R.sub.B)
containing a non-aromatic organic oil of from 5 to 40 mass %, an
organic peroxide of from 0.01 to 0.6 parts by mass, an inorganic
filler of from 10 to 400 parts by mass, a silane coupling agent of
from 1 to 15.0 parts by mass, and a silanol condensation catalyst,
wherein the step (a) has a step (1) and a step (3) below, and when
part of the base resin (R.sub.B) is melt-mixed in the step (1), the
step (a) has the step (1), a step (2), and the step (3) below: Step
(1): a step of melt-mixing all or part of the base resin (R.sub.B),
the organic peroxide, the inorganic filler, and the silane coupling
agent, at a temperature equal to or higher than the decomposition
temperature of the organic peroxide, to prepare a silane master
batch, Step (2); a step of melt-mixing a remainder of the base
resin (R.sub.B) and the silanol condensation catalyst, to prepare a
catalyst master batch, and Step (3): a step of mixing the silane
master batch and either the silanol condensation catalyst or the
catalyst master batch.
10. The method of producing a heat-resistant silane crosslinkable
resin composition according to claim 9, wherein the amount of the
silanol condensation catalyst is from 0.05 to 0.5 parts by mass,
with respect to 100 parts by mass of the base resin (R.sub.B).
11. A heat-resistant silane crosslinkable resin composition
produced by the method according to claim 9.
12. A heat-resistant silane crosslinked resin molded body produced
by the method according to claim 1.
13. A heat-resistant product having the heat-resistant silane
crosslinked resin molded body according to claim 12.
14. The heat-resistant product according to claim 13, wherein the
heat-resistant silane crosslinked resin molded body is provided as
a coating for an electric wire or an optical fiber cable.
15. A silane master batch, for use in a production of a
heat-resistant silane crosslinkable resin composition formed by
melt-mixing, to 100 parts by mass of a base resin (R.sub.B)
containing a non-aromatic organic oil of from 5 to 40 mass %, an
organic peroxide of from 0.01 to 0.6 parts by mass, an inorganic
filler of from 10 to 400 parts by mass, a silane coupling agent of
from 1 to 15.0 parts by mass, and a silanol condensation catalyst,
wherein all or part of the base resin (R.sub.B), the organic
peroxide, the inorganic filler, and the silane coupling agent are
melt-mixed, at a temperature equal to or higher than the
decomposition temperature of the organic peroxide.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation of PCT International
Application No. PCT/JP2014/075752 filed on Sep. 26, 2014, which
claims priority under 35 U.S.C. .sctn.119 (a) to Japanese Patent
Application No. 2013-202670 filed in Japan on Sep. 27, 2013. Each
of the above applications is hereby expressly incorporated by
reference, in its entirety, into the present application.
TECHNICAL FIELD
[0002] The present invention relates to a heat-resistant silane
crosslinked resin molded body and a method of producing the same, a
heat-resistant silane crosslinkable resin composition and a method
of producing the same, a silane master batch, and a heat-resistant
product using a heat-resistant silane crosslinked resin molded
body.
[0003] More specifically, the present invention relates to a
heat-resistant silane crosslinked resin molded body that is
excellent in appearance even when the body is produced under
conditions in which an aggregated substance is easily generated,
and preferably also has excellent mechanical characteristics and
flame retardancy, and a method of producing the same, a silane
master batch and a heat-resistant silane crosslinkable resin
composition capable of being formed into the heat-resistant silane
crosslinked resin molded body, and a method of producing the same,
and a heat-resistant product in which the heat-resistant silane
crosslinked resin molded body is used as an insulator, a sheath or
the like of an electric wire.
BACKGROUND ART
[0004] Insulated wires, cables, cords, optical fiber core wires,
used as inside or outside wiring for electric and electronic
instruments, optical fiber cord and the like, are required to have
various properties such as flame retardancy, heat resistance, and
mechanical characteristics (for example, tensile properties and
abrasion resistance).
[0005] As the materials for these wiring materials, use is made of
resin compositions prepared by incorporating the metal hydrate such
as magnesium hydroxide or aluminum hydroxide in large
quantities.
[0006] In addition, the temperatures of the wiring materials used
for electric or electronic instruments may rise to from 80 to
105.degree. C., even to about 125.degree. C., under continuous use,
so that heat resistance is required in some applications. In such a
case, high heat resistance is imparted to the wiring materials by
applying a method of crosslinking a coating material by electron
beam crosslinking or chemical crosslinking.
[0007] So far, as a method of crosslinking a polyolefin resin such
as polyethylene, or rubber such as ethylene-propylene rubber or
chloroprene rubber, an electron beam crosslinking method of
irradiating with electron beams to cause bridging (also referred to
as crosslinking), a chemical crosslinking method of applying heat,
after molding, to decompose organic peroxide or the like to allow a
crosslinking reaction, and a silane crosslinking method have been
known.
[0008] Among these crosslinking methods, because in most cases
silane crosslinking methods do not particularly require special
facilities, they can therefore be used in a wide variety of
fields.
[0009] The silane crosslinking method is a method of obtaining a
crosslinked molded body, by a grafting reaction of a silane
coupling agent having an unsaturated group onto a polymer in the
presence of organic peroxides, to obtain a silane graft polymer,
and then contacting the silane graft polymer with water in the
presence of a silanol condensation catalyst.
[0010] To give a concrete example, as a method of producing a
halogen-free heat-resistant silane crosslinked resin, there is a
method of melt-blending a silane master batch prepared by grafting
a hydrolyzable silane coupling agent having an unsaturated group
onto a polyolefin resin, a heat-resistant master batch prepared by
kneading a polyolefin resin and an inorganic filler, and a catalyst
master batch containing a silanol condensation catalyst.
[0011] However, in this method, when the inorganic filler exceeds
100 parts by mass with respect to 100 parts by mass of the
polyolefin resin, it becomes difficult to conduct uniform
melt-kneading thereof in a single-screw extruder or a twin-screw
extruder, after the silane master batch and the heat-resistant
master batch are dry mixed. This causes problems such as
deterioration of appearance, significant degeneration of physical
properties, and difficulty of molding with high extrusion load.
[0012] Accordingly, in performing dry blending of the silane master
batch with the heat-resistant master batch, and then uniformly
melt-kneading them, a ratio of the inorganic filler is restricted,
as mentioned above. Therefore, it has been difficult to achieve
high flame retardancy and high heat resistance.
[0013] Generally, for the kneading in the case where the inorganic
filler exceeds 100 parts by mass with respect to 100 parts by mass
of polyolefin resin, an enclosed mixer such as a continuous
kneader, a pressurized kneader, or a Banbury mixer is generally
used.
[0014] In the meantime, when a silane grafting reaction is
performed in a kneader or a Banbury mixer, the hydrolyzable silane
coupling agent having an unsaturated group, which generally has
high volatility, volatizes before grafting reaction. Therefore, it
was very difficult to prepare a desired silane crosslinking master
batch.
[0015] Therefore, in the case of preparing a heat-resistant silane
master batch with a Banbury mixer or a kneader, consideration might
be given to a method which includes adding organic peroxides and a
silane coupling agent having a hydrolysable unsaturated group to
the heat-resistant master batch prepared by melt-blending a
polyolefin resin and an inorganic filler, and then subjecting the
resultant to graft-reaction in a single-screw extruder.
[0016] However, according to such a method, defects in the
appearance of molded body would sometimes occur due to uneven
reaction. Further, the need to incorporate a very large amount of
inorganic filler in the master batch would sometimes result in very
high extrusion load. These make it very difficult to manufacture a
molded body. As a result, it was difficult to obtain a desired
material or molded body. In addition, the method involves two steps
and therefore has a big problem in terms of cost.
[0017] Patent Literature 1 proposes a method in which an inorganic
filler surface-treated with a silane coupling agent, a silane
coupling agent, an organic peroxide, and a crosslinking catalyst
are thoroughly melt-kneaded with a kneader into a resin component
formed by mixing a polyolefin-based resin and a maleic
anhydride-based resin, and then the blend is molded with a
single-screw extruder.
[0018] In addition, Patent Literatures 2 to 4 propose a method of
partially crosslinking a vinyl aromatic thermoplastic elastomer
composition prepared by adding a non-aromatic softener for rubber
as a softener, to a block copolymer or the like as a base resin,
through a silane surface-treated inorganic filler using organic
peroxide.
[0019] Further, Patent Literature 5 proposes a method in which
organic peroxide, a silane coupling agent, and a metal hydrate are
melt-kneaded with a base material in batch, and further melt-molded
together with a silanol condensation catalyst, and then crosslinked
in the presence of water, to easily obtain a cable having heat
resistance.
CITATION LIST
Patent Literatures
[0020] Patent Literature 1: JP-A-2001-101928 ("JP-A" means
unexamined published Japanese patent application)
[0021] Patent Literature 2: JP-A-2000-143935
[0022] Patent Literature 3: JP-A-2000-315424
[0023] Patent Literature 4: JP-A-2001-240719
[0024] Patent Literature 5: JP-A-2012-255077
SUMMARY OF INVENTION
Technical Problem
[0025] However, according to the method described in Patent
Literature 1, a resin is partially crosslinked during melt-kneading
in a Banbury mixer or a kneader, and it is liable to cause poor
appearance (formation of a number of granule-like matters protruded
on a surface thereof) of a molded body to be obtained. Further, a
greater part of silane coupling agent other than the silane
coupling agents with which the inorganic filler is surface-treated,
is liable to be volatilized or condensed. For this reason, the
desired heat resistance cannot be obtained and, in addition, the
appearance of electric wire can be degraded by condensation of the
silane coupling agents.
[0026] In addition, even according to the methods proposed in
Patent Literatures 2 to 4, since the resin still does not form a
sufficient network, there is a problem in that the bond between the
resin and inorganic filler is cleaved at a high temperature.
Therefore, the molded body was sometimes melted at a high
temperature, for example, an insulating material can be melted,
during soldering of an electric wire. Further, there was a problem
in that a molded body is sometimes deformed or generates foams at
the time of secondary processing. Further, when the molded body was
heated for a short period of time at about 200.degree. C.,
appearance thereof could be significantly deteriorated or the body
could be deformed in some cases.
[0027] The method described in Patent Literature 5 has a problem in
which poor appearance due to appearance roughness or the
above-described granule-shaped material (also referred to as an
appearance aggregated substance or simply as an aggregated
substance) was easily generated at the time of extrusion molding of
a silane crosslinkable flame-retardant polyolefin formed of
melt-kneading in batch, together with a silanol condensation
catalyst.
[0028] It has been found that the poor appearance due to generation
of aggregated substance is significantly caused when each component
is melt-mixed at a higher temperature or when time is needed from
melt-kneading of each component to molding of the resultant
blend.
[0029] The present invention aims to solve the problem of the
conventional silane crosslinking method, and to provide a method of
producing a heat-resistant silane crosslinked resin molded body
that is excellent in appearance even when the body is produced
under conditions in which the aggregated substance is easily
generated, and further preferably also has excellent mechanical
characteristics and flame retardancy, and a heat-resistant silane
crosslinked resin molded body that has excellent appearance, and
further preferably has excellent mechanical characteristics and
flame retardancy.
[0030] In addition, the present invention aims to provide a silane
master batch and a heat-resistant silane crosslinkable resin
composition, capable of being formed into the heat-resistant silane
crosslinked resin molded body, and a method of producing the resin
composition.
[0031] Furthermore, the present invention aims to provide a
heat-resistant product using a heat-resistant silane crosslinked
resin molded body obtained by a method of producing a
heat-resistant silane crosslinked resin molded body.
Solution to Problem
[0032] The above-described problems of the present invention can be
solved by the following means.
<1> A method of producing a heat-resistant silane crosslinked
resin molded body, comprising:
[0033] (a) a step of obtaining a mixture by melt-mixing, to 100
parts by mass of a base resin (R.sub.B) containing a non-aromatic
organic oil of from 5 to 40 mass %, an organic peroxide of from
0.01 to 0.6 parts by mass, an inorganic filler of from 10 to 400
parts by mass, a silane coupling agent of from 1 to 15.0 parts by
mass, and a silanol condensation catalyst,
[0034] (b) a step of obtaining a molded body by molding the
mixture, and
[0035] (c) a step of obtaining a heat-resistant silane crosslinked
resin molded body by contacting the molded body with water,
[0036] wherein the step (a) has a step (1) and a step (3) below,
and when part of the base resin (R.sub.B) is melt-mixed in the step
(1), the step (a) has the step (1), a step (2), and the step (3)
below:
[0037] Step (1): a step of melt-mixing all or part of the base
resin (R.sub.B), the organic peroxide, the inorganic filler, and
the silane coupling agent, at a temperature equal to or higher than
the decomposition temperature of the organic peroxide, to prepare a
silane master batch,
[0038] Step (2): a step of melt-mixing a remainder of the base
resin (R.sub.B) and the silanol condensation catalyst, to prepare a
catalyst master batch, and
[0039] Step (3): a step of mixing the silane master batch and
either the silanol condensation catalyst or the catalyst master
batch.
<2> The method of producing a heat-resistant silane
crosslinked resin molded body described in the above item
<1>, wherein the base resin (R.sub.B) contains 5 to 40 mass %
of a styrene-based elastomer, and a mass ratio of the content of
the non-aromatic organic oil to the content of the styrene-based
elastomer is from 1:5 to 2:1. <3> The method of producing a
heat-resistant silane crosslinked resin molded body described in
the above item <1> or <2>, wherein the base resin
(R.sub.B) contains 5 to 40 mass % of an ethylene rubber, and a mass
ratio of the content of the non-aromatic organic oil to the content
of the ethylene rubber is from 1:5 to 1:1. <4> The method of
producing a heat-resistant silane crosslinked resin molded body
described in any one of the above items <1> to <3>,
wherein the base resin (R.sub.B) contains 30 to 95 mass % of a
linear polyethylene having a density in 0.92 g/cm.sup.3 or less or
an ethylene-.alpha.-olefin copolymer. <5> The method of
producing a heat-resistant silane crosslinked resin molded body
described in any one of the above items <1> to <4>,
wherein the mixing amount of the silane coupling agent is more than
4 parts by mass and 15 parts by mass or less, with respect to 100
parts by mass of the base resin (R.sub.B). <6> The method of
producing a heat-resistant silane crosslinked resin molded body
described in any one of the above items <1> to <5>,
wherein the mixing amount of the silane coupling agent is 6 to 15.0
parts by mass, with respect to 100 parts by mass of the base resin
(R.sub.B). <7> The method of producing a heat-resistant
silane crosslinked resin molded body described in any one of the
above items <1> to <6>, wherein substantially no
silanol condensation catalyst is mixed in the step (1). <8>
The method of producing a heat-resistant silane crosslinked resin
molded body described in any one of the above items <1> to
<7>, wherein the amount of the silanol condensation catalyst
is from 0.05 to 0.5 parts by mass, with respect to 100 parts by
mass of the base resin (R.sub.B). <9> A method of producing a
heat-resistant silane crosslinkable resin composition,
comprising:
[0040] (a) a step of obtaining a mixture by melt-mixing, to 100
parts by mass of a base resin (R.sub.B) containing a non-aromatic
organic oil of from 5 to 40 mass %, an organic peroxide of from
0.01 to 0.6 parts by mass, an inorganic filler of from 10 to 400
parts by mass, a silane coupling agent of from 1 to 15.0 parts by
mass, and a silanol condensation catalyst,
[0041] wherein the step (a) has a step (1) and a step (3) below,
and when part of the base resin (R.sub.B) is melt-mixed in the step
(1), the step (a) has the step (1), a step (2), and the step (3)
below:
[0042] Step (1): a step of melt-mixing all or part of the base
resin (R.sub.B), the organic peroxide, the inorganic filler, and
the silane coupling agent, at a temperature equal to or higher than
the decomposition temperature of the organic peroxide, to prepare a
silane master batch,
[0043] Step (2); a step of melt-mixing a remainder of the base
resin (R.sub.B) and the silanol condensation catalyst, to prepare a
catalyst master batch, and
[0044] Step (3): a step of mixing the silane master batch and
either the silanol condensation catalyst or the catalyst master
batch.
<10> The method of producing a heat-resistant silane
crosslinkable resin composition as described in the above item
<9>, wherein the amount of the silanol condensation catalyst
is from 0.05 to 0.5 parts by mass, with respect to 100 parts by
mass of the base resin (R.sub.B). <11> A heat-resistant
silane crosslinkable resin composition produced by the method
described in the above item <9> or <10>. <12> A
heat-resistant silane crosslinked resin molded body produced by the
method described in any one of the above items <1> to
<8>. <13> A heat-resistant product having the
heat-resistant silane crosslinked resin molded body described in
the above item <12>. <14> The heat-resistant product
described in the above item <13>, wherein the heat-resistant
silane crosslinked resin molded body is provided as a coating for
an electric wire or an optical fiber cable. <15> A silane
master batch, for use in a production of a heat-resistant silane
crosslinkable resin composition formed by melt-mixing, to 100 parts
by mass of a base resin (R.sub.B) containing a non-aromatic organic
oil of from 5 to 40 mass %, an organic peroxide of from 0.01 to 0.6
parts by mass, an inorganic filler of from 10 to 400 parts by mass,
a silane coupling agent of from 1 to 15.0 parts by mass, and a
silanol condensation catalyst,
[0045] wherein all or part of the base resin (R.sub.B), the organic
peroxide, the inorganic filler, and the silane coupling agent are
melt-mixed, at a temperature equal to or higher than the
decomposition temperature of the organic peroxide.
[0046] In the present invention, "base resin (R.sub.B)" means a
resin for forming the heat-resistant silane crosslinked resin
molded body or the heat-resistant silane crosslinkable resin
composition.
[0047] In the present invention, "part of the base resin (R.sub.B)"
means a resin to be used in the step (1) in the base resin
(R.sub.B), and part of the base resin (R.sub.B) itself (i.e. it has
a composition same as the base resin (R.sub.B)), part of resin
components that constitute the base resin (R.sub.B), and a resin
component that constitutes the base resin (R.sub.B) (for example, a
total amount of a specific resin component among a plurality of the
resin components).
[0048] In addition, "remainder of the base resin (R.sub.B)" means a
remaining base resin excluding the part to be used in the step (1)
in the base resin (R.sub.B), and specifically, a remainder of the
base resin (R.sub.B) itself (i.e. it has a composition same as the
base resin (R.sub.B)), a remainder of the resin components that
constitute the base resin (R.sub.B), and a remaining resin
component that constitutes the base resin (R.sub.B).
[0049] Note that, in this patent specification, numerical
expressions in a style of " . . . to . . . " will be used to
indicate a range including the lower and upper limits represented
by the numerals given before and after "to", respectively.
Advantageous Effects of Invention
[0050] According to the present invention, a non-aromatic organic
oil is mixed with a base resin. According to a production method of
the present invention, local heat generation, particularly during
melt-blending in a step (a) can be suppressed, to reduce generation
of an aggregated substance. In addition, a hydrolysis reaction of a
silane coupling agent before molding can be suppressed by
preventing moisture from being mixed or also incorporated from
outside during melt-kneading (during compounding) and during
storage of a melt-kneaded product (compound). Further, the
non-aromatic organic oil functions as an appearance improver during
molding, and appearance of a molded body can be improved. A
heat-resistant silane crosslinked resin molded body that also has
excellent mechanical characteristics and flame retardancy can be
further preferably produced.
[0051] In addition, according to the present invention, an
inorganic filler and a silane coupling agent are mixed before
and/or during kneading with the base resin (R.sub.B). Thus,
volatilization of the silane coupling agent during kneading can be
suppressed, and the heat-resistant silane crosslinked resin molded
body can be efficiently produced. Further, a high heat-resistant
silane crosslinked resin molded body to which the inorganic filler
is added in a large amount can be produced, without using a special
machine such as an electron beam crosslinking machine.
[0052] Therefore, according to the present invention, the problems
of a conventional silane crosslinking method can be solved, and
generation of the aggregated substance is suppressed even when the
body is produced under conditions in which the aggregated substance
is easily generated, and a heat-resistant silane crosslinked resin
molded body that is excellent in appearance, and preferably also
has excellent mechanical characteristics and flame retardancy can
be produced.
[0053] According to the present invention, a silane master batch
and a heat-resistant silane crosslinkable resin composition,
capable of being formed into the heat-resistant silane crosslinked
resin molded body having excellent appearance and flame retardancy
can be provided.
[0054] In addition, according to the present invention, a
heat-resistant product using a heat-resistant silane crosslinked
resin molded body can be provided.
[0055] Other and further features and advantages of the invention
will appear more fully from the following description.
MODE FOR CARRYING OUT THE INVENTION
[0056] The preferable embodiment of the present invention is
described in detail below.
[0057] In both of the "method of producing a heat-resistant silane
crosslinked resin molded body" of the present invention and the
"method of producing a heat-resistant silane crosslinkable resin
composition" of the present invention, the below shown step (a),
which at least includes the following step (1) and (3), is carried
out.
[0058] Accordingly, the "method of producing a heat-resistant
silane crosslinked resin molded body" of the present invention and
the "method of producing a heat-resistant silane crosslinkable
resin composition" of the present invention (in the description of
parts common to both, the methods may be collectively referred to
as a production method of the present invention in some cases) are
collectively described below.
[0059] Step (a): Step of obtaining a mixture by melt-mixing, to 100
parts by mass of a base resin (R.sub.B) containing a non-aromatic
organic oil of from 5 to 40 mass %, an organic peroxide of from
0.01 to 0.6 parts by mass, an inorganic filler of from 10 to 400
parts by mass, a silane coupling agent of from 1 to 15.0 parts by
mass, and a silanol condensation catalyst.
[0060] Step (b): Step of obtaining a molded body by molding the
mixture.
[0061] Step (c): Step of obtaining a heat-resistant silane
crosslinked resin molded body by contacting the molded body with
water.
[0062] Then, this step (a) has at least step (1) and step (3) below
when all of the base resin (R.sub.B) is melt-mixed in step (1)
below, and when part of the base resin (R.sub.B) is melt-mixed in
step (1) below, step (a) has at least step (1), step (2), and step
(3) below.
[0063] Step (1): Step of melt-mixing all or part of the base resin
(R.sub.B), the organic peroxide, the inorganic filler, and the
silane coupling agent, at a temperature equal to or higher than the
decomposition temperature of the organic peroxide, to prepare a
silane master batch,
[0064] Step (2): Step of melt-mixing a remainder of the base resin
(R.sub.B) and the silanol condensation catalyst, to prepare a
catalyst master batch, and
[0065] Step (3): Step of mixing the silane master batch and either
the silanol condensation catalyst or the catalyst master batch.
[0066] Here, "mixing" means an operation for obtaining a uniform
mixture.
[0067] First, the components used in the present invention will be
described.
<Base Resin (R.sub.B)--
[0068] The base resin (R.sub.B) to be used in the present invention
at least contains a non-aromatic organic oil used as an oil
component, and a resin component.
[0069] In this base resin (R.sub.B), the content of each component
is selected from the following ranges, so that the total amount of
components would be 100 mass %.
(Non-Aromatic Organic Oil)
[0070] An organic oil is a mixed oil containing three oils: an oil
composed of hydrocarbon having an aromatic ring, an oil composed of
hydrocarbon having a naphthene ring, and an oil composed of
hydrocarbon having a paraffin chain. An aromatic organic oil means
one in which the number of carbon atoms that constitute the
aromatic ring is 30% or more based on the total number of carbon
atoms that constitute the aromatic ring, the naphthene ring and the
paraffin chain. The non-aromatic organic oil to be used in the
present invention means one in which the number of carbon atoms
that constitute the aromatic ring is less than 30% based on the
above-described total number of carbon atoms.
[0071] Specific examples of such a non-aromatic organic oil include
a naphthene oil in which the number of carbon atoms that constitute
a naphthene ring is from 30 to 40% based on the above-described
total number of carbon atoms, and the number of carbon atoms that
constitute a paraffin chain is less than 50% based on the
above-described total number of carbon atoms, and a paraffin oil in
which the number of carbon atoms that constitute a paraffin chain
is 50% or more based on the above-described total number of carbon
atoms. As the non-aromatic organic oil, a paraffin oil is
preferable.
[0072] From a viewpoint of prevention of swelling under a high
temperature, the non-aromatic organic oil has an aniline point of
preferably 80.degree. C. or higher, and further preferably
100.degree. C. or higher. If the aniline point is 80.degree. C. or
higher, it is possible to suppress swelling of the heat-resistant
silane crosslinked resin molded body due to impregnation of oil in
a high temperature oil. The aniline point can be measured in
accordance with the test tube method specified in JIS K 2256:
1996.
[0073] In addition, an average molecular weight of the non-aromatic
organic oil is preferably from 200 to 2,000, and further preferably
from 250 to 1,000. When the average molecular weight is within the
above-described range, volatilization of the non-aromatic organic
oil during kneading or the like can be prevented, and an effect of
preventing moisture from being mixed can also be improved.
[0074] The average molecular weight is expressed in terms of a
value determined by a vapor pressure equilibrium method by using a
preliminarily prepared calibration curve.
[0075] Examples of the non-aromatic organic oil that can be used in
the present invention include DIANA PROCESS OIL PW90, PW380 (trade
names, manufactured by Idemitsu Kosan Co., Ltd.), COSMO NEUTRAL 500
(trade name, manufactured by COSMO OIL Co., Ltd.) and the like.
[0076] The content of the non-aromatic organic oil in the base
resin (R.sub.B) is from 5 to 40 mass %, preferably from 5 to 35
parts by mass, and further preferably from 7 to 33 parts by mass.
When the content of the non-aromatic organic oil is too low, an
effect of the non-aromatic organic oil is not thoroughly exhibited
in some cases. On the other hand, when the content is too high,
shear heat is not appreciably generated upon gelating during
melt-kneading, and a temperature of the melt-kneaded product does
not thoroughly rise, and therefore a silane grafting reaction does
not progress in some cases. With regard to the content of the
non-aromatic organic oil, within the above-mentioned ranges, a
content ratio relative to an ethylene rubber or a styrene-based
elastomer further preferably satisfies any of the ranges mentioned
later.
(Resin Component)
[0077] The resin component to be used in the present invention is
not particularly limited, as long as the resin component is a
component having a crosslinking site that can react with a
crosslinking group of a hydrolyzable silane coupling agent in the
presence of the organic peroxide, for example, an unsaturated
bonding site in a carbon chain, or a carbon atom having a hydrogen
atom in a main chain or at an end. Example of such a resin
component include a polyolefin resin (PO), a polyester resin (PE),
a polyamide resin (PA), a polystyrene resin (PS), a polyol resin,
or the like.
[0078] The resin component to be used in the present invention also
contains, in addition to the above-described each resin component,
various rubber and elastomers formed of a polymer or copolymer
having the above-described crosslinking site, for example, ethylene
rubber and the styrene-based elastomer.
[0079] The resin component to be used in the present invention is
preferably a polyolefin resin, ethylene rubber and a styrene-based
elastomer.
[0080] The resin component may be used singly alone, or be used by
combining two or more kinds thereof. When two or more kinds of the
resin components are used in combination, it is preferable to use
the polyolefin resin in combination with any one or both of the
ethylene rubber and the styrene-based elastomer.
[0081] The polyolefin resin as the resin component is not
particularly limited, as long as the polyolefin resin is a resin
composed of a polymer obtained by polymerizing or copolymerizing a
compound having an ethylenically unsaturated bond, and the
polyolefin resins that are conventionally known and used for
heat-resistant resin compositions can be used.
[0082] Examples thereof include resins of a polyethylene, a
polypropylene, an ethylene-.alpha.-olefin copolymer, a block
copolymer of polypropylene with ethylene-.alpha.-olefin resin, and
a polyolefin copolymer having an acid copolymerization component or
an acid ester copolymerization component.
[0083] Among them, in view of grafting efficiency, insulation
resistance, high accepting properties to various inorganic fillers
including metal hydrate, and capability of maintaining mechanical
strength even when the inorganic fillers are incorporated thereinto
in a large amount, a resin of a polyethylene, of an
ethylene-.alpha.-olefin copolymer, or of a polyolefin copolymer
having an acid copolymerization component or an acid ester
copolymerization component is preferable, and a resin of a linear
polyethylene having a density of 0.92 g/cm.sup.3 or less or of an
ethylene-.alpha.-olefin copolymer is further preferable.
[0084] The polyolefin resin may be used singly alone, or be used by
combining two or more kinds thereof.
[0085] Polyethylene is not particularly limited, as long as the
polyethylene is a polymer containing an ethylene component as a
constituent. The polyethylene includes a homopolymer consisting of
ethylene, a copolymer of ethylene and 5 mol % or less of
.alpha.-olefin (excluding propylene), and a copolymer of ethylene
and 1 mol % or less of non-olefin having carbon, oxygen, and
hydrogen atoms only in a functional group (for example, JIS K
6748). As the above-mentioned .alpha.-olefin and non-olefin,
conventionally known ones that have been used so far as
copolymerization components for polyethylene can be used without
any particular restriction.
[0086] In the present invention, the density of the polyethylene is
not particularly limited, but is preferably 0.92 g/cm.sup.3 or
less, and further preferably from 0.87 to 0.91 g/cm.sup.3. The
density of the polyethylene can be measured based on JIS K
7112.
[0087] Examples of the polyethylene that can be used in the present
invention include high-density polyethylene (HDPE), low-density
polyethylene (LDPE), ultra high molecular weight polyethylene
(UHMW-PE), linear low-density polyethylene (LLDPE), and
very-low-density polyethylene (VLDPE). Among them, linear
low-density polyethylene or low-density polyethylene is
preferable.
[0088] The polyethylene may be used singly alone or be used by
combining two or more kinds thereof.
[0089] Specific examples of the ethylene-.alpha.-olefin copolymer
preferably include a copolymer of ethylene and an .alpha.-olefin
having 3 to 12 carbon atoms (excluding one included in the
above-mentioned polyethylene), and the density thereof is not
particularly limited.
[0090] Examples of the .alpha.-olefin component of the
ethylene-.alpha.-olefin copolymer include components such as
propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene,
1-decene, 1-dodecene, and the like. The ethylene-.alpha.-olefin
copolymer is preferably a copolymer of ethylene with .alpha.-olefin
component having 3 to 12 carbon atoms (excluding one included in
the polyethylene). Specific examples thereof include an
ethylene-propylene copolymer, an ethylene-butylene copolymer, and
an ethylene-.alpha.-olefin copolymer that is synthesized in the
presence of a single-site catalyst. The ethylene-.alpha.-olefin
copolymer may be used singly alone or be used by combining two or
more kinds thereof.
[0091] Specific examples of the acid copolymerization component and
the acid ester copolymerization component in the polyolefin
copolymer having the acid copolymerization component or the acid
ester copolymerization component include a carboxylic acid compound
such as (meth)acrylic acid and an acid ester compound such as vinyl
acetate and alkyl (meth)acrylate. Herein, the alkyl group of the
alkyl (meth)acrylate is preferably those having 1 to 12 carbon
atoms, and example of those may include methyl group, ethyl group,
propyl group, butyl group, or hexyl group. Example of the
polyolefin copolymer having an acid copolymerization component or
an acid ester copolymerization component (excluding one included in
the polyethylene) include ethylene-vinyl acetate copolymer,
ethylene-(meth)acrylic acid copolymers, ethylene-alkyl
(meth)acrylate copolymers or the like. Among them, ethylene-vinyl
acetate copolymers, ethylene-methyl acrylate copolymers,
ethylene-ethyl acrylate copolymers, and ethylene-butyl acrylate
copolymers are preferable; and ethylene-vinyl acetate copolymers
and ethylene-ethyl acrylate copolymers are particularly preferable
from the standpoint of the acceptability to the inorganic filler
and heat resistance. The density of the polyolefin copolymer having
an acid copolymerization component or an acid ester
copolymerization component is not particularly limited. The
polyolefin copolymer having an acid copolymerization component or
an acid ester copolymerization component may be used singly alone
or be used by combining two or more kinds thereof.
[0092] When the base resin (R.sub.B) contains the polyolefin resin,
the content of the polyolefin resin in the base resin (R.sub.B) is
not particularly limited, but is preferably from 20 to 95 mass %,
and further preferably from 25 to 85 mass %. When the polyolefin
resin is contained at this content, a consolidated network can be
formed, and high heat resistance can be obtained.
[0093] When the polyolefin resin is one of the resin composed of
the linear polyethylene having the density of 0.92 g/cm.sup.3 or
less and the resin composed of the ethylene-.alpha.-olefin
copolymer, the content thereof in the base resin (R.sub.B) is not
particularly limited, but is preferably from 30 to 95 mass %, and
further preferably from 32 to 85 mass %.
[0094] The ethylene rubber is not particularly limited, as long as
the ethylene rubber is rubber composed of the copolymer obtained by
copolymerizing a compound having an ethylenically unsaturated bond,
and a conventionally known one can be used. Specific examples of
the ethylene rubber preferably include a rubber composed of a
copolymer of ethylene and .alpha.-olefin, and a rubber composed of
a terpolymer of ethylene, .alpha.-olefin and diene. The diene
constituent of the terpolymer may be a conjugated diene constituent
or a non-conjugated diene constituent, and a non-conjugated diene
constituent is preferable. In other words, specific examples of the
terpolymer include a terpolymer of ethylene, .alpha.-olefin, and
conjugated diene, and a terpolymer of ethylene, .alpha.-olefin, and
non-conjugated diene; and a copolymer of ethylene and
.alpha.-olefin, and a terpolymer of ethylene, .alpha.-olefin, and
non-conjugated diene are preferable.
[0095] As a specific example of the .alpha.-olefin constituent,
each .alpha.-olefin constituent having 3 to 12 carbon atoms is
preferable, and specific examples include those exemplified in
ethylene-.alpha.-olefin copolymer. Specific examples of the
conjugated diene constituent include those exemplified in
styrene-based elastomer as described later, and butadiene or the
like is preferable. Specific examples of the non-conjugated diene
constituent include dicyclopentadiene (DCPD), ethylidene norbornene
(ENB), 1,4-hexadiene, and the like, and ethylidene norbornene is
preferable.
[0096] Specific examples of the rubber composed of the copolymer of
ethylene and .alpha.-olefin include ethylene-propylene rubber,
ethylene-butene rubber, and ethylene-octene rubber. Specific
examples of the rubber composed of the terpolymer of ethylene,
.alpha.-olefin, and diene include ethylene-propylene-diene rubber
and ethylene-butene-diene rubber.
[0097] Among them, ethylene-propylene rubber, ethylene-butene
rubber, ethylene-propylene-diene rubber, and ethylene-butene-diene
rubber are preferable, and ethylene-propylene rubber and
ethylene-propylene-diene rubber are further preferable.
[0098] In the ethylene rubber, an amount of the ethylene
constituent (referred to as an ethylene amount) in the copolymer is
preferably from 45 to 70 mass %, and further preferably from 50 to
68 mass %. As a method of measuring the ethylene amount, a value
measured in accordance with the method described in ASTM D3900 is
adopted.
[0099] The content of the ethylene rubber in the base resin
(R.sub.B) is not particularly limited, but is preferably from 0 to
40 mass %, further preferably from 5 to 40 mass %, and still
further preferably from 10 to 38 mass %. When the ethylene rubber
is contained at the above-mentioned content, generation of the
aggregated substances due to a crosslinking reaction between the
resin components and a condensation reaction between the silane
coupling agents during melt-blending can be suppressed, and
appearance of the molded body is excellent.
[0100] The ethylene rubber only needs to satisfy the
above-mentioned content, and a ratio of the content of the
non-aromatic organic oil to the content of the ethylene rubber
(non-aromatic organic oil:ethylene rubber) is preferably from 1:5
to 1:1, further preferably from 1:4 to 3:4, and still further
preferably from 3:10 to 2:1. When this ratio is less than 1:5, a
state is formed in which the non-aromatic organic oil is
substantially oil-added to the ethylene rubber, and force of
preventing moisture from being mixed becomes somewhat weak in some
cases. On the other hand, when this ratio exceeds 1:1, the molded
body has a possibility of causing bleed of the aromatic organic oil
in long-term storage after molding.
[0101] The styrene-based elastomer means one composed of a polymer
containing, as a constituent, an aromatic vinyl compound in its
molecule. Accordingly, in the present invention, even if a polymer
contains an ethylene constituent in the molecule, if the polymer
contains an aromatic vinyl compound constituent, such a polymer is
classified into the styrene-based elastomer.
[0102] Examples of the styrene-based elastomer may include a block
copolymer of and a random copolymer of a conjugated diene compound
with an aromatic vinyl compound, and a hydrogenated derivative
thereof. Examples of the constituent of the aromatic vinyl compound
may include styrene, p-(tert-butyl)styrene, .alpha.-methylstyrene,
p-methylstyrene, divinylbenzene, 1,1-diphenylstyrene,
N,N-diethyl-p-aminoethylstyrene, vinyltoluene, and the like. Among
them, a styrene constituent is preferable. The constituent of the
aromatic vinyl compound is used one kind alone, or is used by
combining two or more kinds thereof. Examples of the constituent of
the conjugated diene compound include butadiene, isoprene,
1,3-pentadiene, and 2,3-dimethyl-1,3-butadiene. Among them,
butadiene constituent is preferable as the conjugated diene
compound. The constituent of the conjugated diene compound may be
used singly alone, or be used by combining two or more kinds
thereof. Furthermore, as the styrene-based elastomer, an elastomer
obtained in the same manner and does not contain a styrene
component but contains an aromatic vinyl compound other than
styrene may be used.
[0103] The styrene-based elastomer preferably has a content of the
styrene constituent of 30% or more. When the styrene content is too
low, oil resistance is reduced, or abrasion resistance is reduced,
in some cases.
[0104] Specific examples of the styrene-based elastomers include a
styrene-ethylene-butylene-styrene block copolymer (SEBS), a
styrene-isoprene-styrene block copolymer (SIS), a hydrogenated SBS,
a styrene-ethylene-ethylene-propylene-styrene block copolymer
(SEEPS), a styrene-ethylene-propylene-styrene block copolymer
(SEPS), a hydrogenated SIS, a hydrogenated styrene-butadiene rubber
(HSBR), and a hydrogenated acrylonitrile-butadiene rubber
(HNBR).
[0105] As the styrene-based elastomer, commercially available
products can be used. For example, use can be made of Septon 4077,
Septon 4055, Septon 8105 (trade names, manufactured by Kuraray Co.,
Ltd.), Dynaron 1320P, Dynaron 4600P, 6200P, 8601P, and 9901P (trade
names, manufactured by JSR Corporation.), and the like.
[0106] The content of the styrene-based elastomer in the base resin
(R.sub.B) is not particularly limited, but is preferably from 0 to
45 mass %, and further preferably from 5 to 40 mass %. When the
content of the styrene-based elastomer is too high, the heat
resistance or long-term heat resistance is adversely affected in
some cases.
[0107] The content of the styrene-based elastomer only needs to
satisfy the above-mentioned content, and a ratio of the content of
the non-aromatic organic oil to the content of the styrene-based
elastomer (non-aromatic organic oil:styrene-based elastomer) is
preferably from 1:5 to 2:1, further preferably from 1:4 to 2:3, and
still further preferably from 3:10 to 5:6. When this ratio is less
than 1:5, a state is formed in which the non-aromatic organic oil
is substantially oil-added to the styrene-based elastomer, and
force of preventing moisture from being mixed becomes somewhat weak
in some cases. On the other hand, when this ratio exceeds 2:1, the
molded body has a possibility of causing bleed of the aromatic
organic oil in long-term storage after molding.
[0108] The resin may contain, in addition to the above-mentioned
components, an additive as mentioned later or a resin component
other than the above-described resin component.
<Organic Peroxide>
[0109] The organic peroxide plays a role of generating a radical at
least by thermal decomposition, to cause a grafting reaction of the
silane coupling agent onto the resin component, as a catalyst. In
particular, when the silane coupling agent contains an
ethylenically unsaturated group, the organic peroxide play a role
of causing the grafting reaction due to a radical reaction
(including an abstraction reaction of a hydrogen radical from the
resin component) between the ethylenically unsaturated group and
the resin component.
[0110] The organic peroxide to be used in the present invention is
not particularly limited, as long as the organic peroxide is one
that generates a radical. For example, as the organic peroxide, the
compound represented by the formula R.sup.1--OO--R.sup.2,
R.sup.1--OO--C(.dbd.O)R.sup.3, or
R.sup.4C(.dbd.O)--OO(C.dbd.O)R.sup.5 is preferable. Herein,
R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 each independently
represent an alkyl group, an aryl group, or an acyl group. Among
them, in the present invention, it is preferable that all of
R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 be an alkyl group,
or any one of them be an alkyl group, and the rest be an acyl
group.
[0111] Examples of such organic peroxide may include dicumyl
peroxide (DCP), di-tert-butyl peroxide,
2,5-dimethyl-2,5-di-(tert-butyl peroxy)hexane,
2,5-dimethyl-2,5-di(tert-butyl peroxy)hexine-3, 1,3-bis(tert-butyl
peroxyisopropyl)benzene, 1,1-bis(tert-butyl
peroxy)-3,3,5-trimethylcyclohexane, n-butyl-4,4-bis(tert-butyl
peroxy)valerate, benzoyl peroxide, p-chlorobenzoyl peroxide,
2,4-dichlorobenzoyl peroxide, tert-butyl peroxybenzoate, tert-butyl
peroxyisopropyl carbonate, diacetyl peroxide, lauroyl peroxide,
tert-butylcumyl peroxide and the like. Among them, dicumyl peroxide
(DCP), 2,5-dimethyl-2,5-di-(tert-butyl peroxy)hexane, or
2,5-dimethyl-2,5-di-(tert-butyl peroxy)hexine-3 is preferable, from
the standpoint of odor, coloration, and scorch stability.
[0112] The decomposition temperature of the organic peroxide is
preferably 80 to 195.degree. C., and more preferably 125 to
180.degree. C.
[0113] For the present invention, the decomposition temperature of
the organic peroxide means the temperature, at which, when an
organic peroxide having a single composition is heated, the organic
peroxide itself causes a decomposition reaction and decomposes into
two or more kinds of compounds at a certain temperature or
temperature range. In specific, the decomposition temperature is a
temperature at which heat absorption or exothermic reaction starts,
when the organic peroxide is heated at room temperature in a
heating rate of 5.degree. C./min under a nitrogen gas atmosphere,
by a thermal analysis such as a DSC method.
<Inorganic Filler>
[0114] In the present invention, the inorganic filler is not
particularly limited as long as it has, on its surface, a site that
can form a hydrogen bond or the like or a site that can be
chemically linked by a covalent bond, with a reaction site such as
a silanol group of a silane coupling agent. For the inorganic
filler, examples of the site that can be chemically linked to the
reaction site of the silane coupling agent may include an OH group
(OH group of hydroxy group, of water molecule in hydrous substance
or crystallized water, or of carboxyl group), amino group, a SH
group, and the like.
[0115] As such an inorganic filler, use can be made of metal
hydrate, such as a compound having a hydroxy group or crystallized
water, for example, aluminum hydroxide, magnesium hydroxide,
calcium carbonate, magnesium carbonate, calcium silicate, magnesium
silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum
nitride, aluminum borate whisker, hydrated aluminum silicate,
hydrated magnesium silicate, basic magnesium carbonate, and
hydrotalcite; boron nitride, silica (crystalline silica, amorphous
silica, and the like), carbon, clay, zinc oxide, tin oxide,
titanium oxide, molybdenum oxide, antimony trioxide, a silicone
compound, quartz, talc, zinc borate, white carbon, zinc borate,
zinc hydroxystannate, or zinc stannate.
[0116] Among them, as the inorganic filler, at least one kind of
silica, aluminum hydroxide, magnesium hydroxide, calcium carbonate,
magnesium carbonate, zinc borate, and zinc hydroxystannate is
preferable, and at least one kind selected from the group
consisting of silica, aluminum hydroxide, magnesium hydroxide,
calcium carbonate and antimony trioxide is further preferable.
[0117] The inorganic filler may be used singly alone, or in
combination of two or more kinds thereof.
[0118] The inorganic filler has an average particle diameter of
preferably 0.2 to 10 .mu.m, more preferably 0.3 to 8 .mu.m, further
preferably 0.4 to 5 .mu.m, and particularly preferably 0.4 to 3
.mu.m. When the average particle diameter of the inorganic filler
is too small, the inorganic fillers can cause secondary aggregation
at the time of mixing with a silane coupling agent, and thus the
appearance of a molded articles can be deteriorated or the
aggregated substances can be generated. On the other hand, when the
average particle diameter is too large, the appearance can be
deteriorated, or the effect on maintaining the silane coupling
agent can be reduced, thereby generating a problem in crosslinking.
The average particle diameter is obtained by dispersing the
inorganic filler in alcohol or water, and then measuring using an
optical particle diameter measuring device such as a laser
diffraction/scattering particle diameter distribution measuring
device.
[0119] As the inorganic filler, a surface-treated inorganic filler,
surface-treated with a silane coupling agent can be used. Specific
examples of silane-coupling-agent-surface-treated metal hydrate
include KISUMA 5L, KISUMA 5P (both trade names, magnesium
hydroxide, manufactured by Kyowa Chemical Industry Co., Ltd. or the
like) and aluminum hydroxide. The amount of surface treatment of
the inorganic filler with a silane coupling agent is not
particularly limited, but is 2 mass % or less, for example.
<Silane Coupling Agent>
[0120] The silane coupling agent to be used in the present
invention only needs to have a group that can perform a grafting
reaction onto a resin component in the presence of a radical, and a
group that can be chemically bonded with inorganic filler, and
preferably is a hydrolyzable silane coupling agent having a
hydrolyzable group at an end. The silane coupling agent is further
preferably one having, at an end, a group containing an amino
group, a glycidyl group, or an ethylenically unsaturated group, and
a group containing a hydrolyzable group;
[0121] and still further preferably a silane coupling agent having
a group containing an ethylenically unsaturated group, and a group
containing a hydrolyzable group, at an end. The group containing an
ethylenically unsaturated group is not particularly limited, and
specific examples thereof include a vinyl group, an allyl group, a
(meth)acryloyloxy group, a (meth)acryloyloxyalkylene group, and a
p-styryl group. In addition, these silane coupling agents and a
silane coupling agent having any other end group may be
simultaneously used.
[0122] As such a silane coupling agent, for example, a compound
represented by the following Formula (1) can be used.
##STR00001##
[0123] In Formula (1), R.sub.a11 represents a group having an
ethylenically unsaturated group, R.sub.b11 represents an aliphatic
hydrocarbon group, a hydrogen atom, or Y.sup.13. Y.sup.11,
Y.sup.12, and Y.sup.13 each represent a hydrolyzable organic group.
Y.sup.11, Y.sup.12, and Y.sup.13 may be the same or different from
each other.
[0124] R.sub.a11 of the silane coupling agent represented by
Formula (1) is preferably a group having an ethylenically
unsaturated group. The group having an ethylenically unsaturated
group is as explained above, and is preferably a vinyl group.
[0125] R.sub.b11 represents an aliphatic hydrocarbon group, a
hydrogen atom, or Y.sup.13 to be described below. Example of the
aliphatic hydrocarbon group may include a monovalent aliphatic
hydrocarbon group having 1 to 8 carbon atoms other than an
aliphatic unsaturated hydrocarbon. R.sub.b11 is preferably Y.sup.13
to be described below.
[0126] Y.sup.11, Y.sup.12, and Y.sup.13 each independently
represent a hydrolyzable organic group, and examples thereof may
include an alkoxy group having 1 to 6 carbon atoms, an aryloxy
group having 6 to 10 carbon atoms, and an acyloxy group having 1 to
4 carbon atoms. Among them, an alkoxy group is preferable. Specific
examples of the hydrolyzable organic group may include methoxy,
ethoxy, butoxy, and acyloxy. Among them, from the standpoint of the
reactivity of the silane coupling agent, methoxy or ethoxy is more
preferable, and methoxy is particularly preferable.
[0127] As the silane coupling agent, a silane coupling agent that
has high hydrolysis rate is preferable, and a silane coupling
agent, in which R.sub.b11 is Y.sup.13 and also Y.sup.11, Y.sup.12,
and Y.sup.13 are the same each other, is more preferable. A
hydrolyzable silane coupling agent in which at least one of
Y.sup.11, Y.sup.12, and Y.sup.13 is a methoxy group is further
preferable, and a hydrolyzable silane coupling agent in which all
of Y.sup.11, Y.sup.12, and Y.sup.13 are methoxy groups is
particularly preferable.
[0128] Specific examples of the silane coupling agent having a
vinyl group, a (meth)acryloyloxy group or a
(meth)acryloyloxyalkylene group at an end include organosilanes
such as vinyltrimethoxysilane, vi nyltriethoxysilane,
vinyltributoxysilane, vinyldimethoxyethoxysilane,
vinyldimethoxybutoxysilane, vinyldiethoxybutoxysilane,
allyltrimethoxysilane, allyltriethoxysilane, vinyltriacetoxysilane;
methacryloxypropyltrimethoxysilane,
methacryloxypropyltriethoxysilane, and
methacryloxypropylmethyldimethoxysilane. The silane coupling agent
may be used singly alone, or two or more kinds thereof. Among these
crosslinking silane coupling agents, a silane coupling agent having
a vinyl group and an alkoxy group on an end thereof is more
preferable, and vinyltrimethoxysilane and vinyltriethoxysilane are
still more preferable.
[0129] Specific examples of one having a glycidyl group at an end
include 3-glycidoxypropyltriethoxysilane,
3-glycidoxypropylmethyldiethoxysilane,
3-glycidoxypropyltrimethoxysilane,
3-glycidoxypropylmethyldimethoxysilane, and
2-(3,4-epoxycyclohexyDethyltrimethoxysilane.
[0130] The silane coupling agent may be used as it is, or may be
diluted with a solvent and used.
<Silanol Condensation Catalyst>
[0131] The silanol condensation catalyst has an action of binding
the silane coupling agents which have been grafted onto the resin
component to each other, by a condensation reaction in the presence
of water. Based on the action of the silanol condensation catalyst,
the resin components are crosslinked between themselves through
silane coupling agent. As a result, the heat-resistant silane
crosslinked resin molded body having excellent heat resistance can
be obtained.
[0132] As the silanol condensation catalyst to be used in the
present invention, an organic tin compound, a metal soap, a
platinum compound, and the like can be mentioned. General examples
of the silanol condensation catalyst may include dibutyltin
dilaurate, dioctyltin dilaurate, dibutyltin dioctylate, dibutyltin
diacetate, zinc stearate, lead stearate, barium stearate, calcium
stearate, sodium stearate, lead naphthenate, lead sulfate, zinc
sulfate, an organic platinum compound, and the like. Among them,
the organic tin compounds such as dibutyltin dilaurate, dioctyltin
dilaurate, dibutyltin dioctylate, and dibutyltin diacetate are
particularly preferable.
<Carrier Resin>
[0133] The silanol condensation catalyst to be used in the present
invention is mixed with a resin, if desired. Such a resin (also
referred to as a carrier resin) is not particularly limited, but a
part of the base resin (R.sub.B) can be used. The part of the base
resin (R.sub.B) may be one or more component of the resin
components that constitute the base resin (R.sub.B), or a part of
the whole resin components that constitute the base resin
(R.sub.B), but one or more component of the resin components that
constitute the base resin (R.sub.B) is preferable. As the resin
component in this case, the polyolefin resin is preferable, and in
view of good affinity with the silanol condensation catalyst and
also of excellent heat resistance, a resin containing ethylene as a
constituent is further preferable among the polyolefin, and
polyethylene is particularly preferable.
<Additive>
[0134] To the heat-resistant silane crosslinked resin molded body
and the heat-resistant silane crosslinkable resin composition,
various additives which are generally used for electric wires,
electric cables, electric cords, sheets, foams, tubes, and pipes,
may be properly used in the range that does not adversely affect
the purpose of the present invention. Examples of these additives
include a crosslinking assistant, an antioxidant, a lubricant, a
metal inactivator, a filler, and other resins.
[0135] These additives, particularly the antioxidant and the metal
inactivator may be mixed with any of the components, but may
preferably be mixed with the carrier resin. It is preferable that
the crosslinking assistant is not substantially contained.
Especially, it is preferable that the crosslinking assistant be not
substantially mixed in the step (a) of producing the silane master
batch. If the crosslinking assistant is not substantially mixed,
crosslinking of the resin components with each other during
kneading hardly occurs, and the appearance and the heat resistance
of the heat-resistant silane crosslinked resin molded body are
excellent. Here, the term "is not substantially contained or is not
substantially mixed" means that the crosslinking assistant is not
actively added or mixed and it is not intended to exclude the
crosslinking assistant which is inevitably contained or mixed.
[0136] The crosslinking assistant refers to one that forms a
partial crosslinking structure with the resin component, in the
presence of the organic peroxide. Examples thereof may include
polyfunctional compounds, for example, a methacrylate compound such
as polypropyleneglycol diacrylate and trimethylolpropane
triacrylate, an allyl compound such as triallyl cyanurate, a
maleimide compound, or a divinyl compound.
[0137] Examples of the antioxidant may include an amine-based
antioxidant such as 4,4'-dioctyl-diphenylamine,
N,N'-diphenyl-p-phenylenediamine,
2,2,4-trimethyl-1,2-dihydroquinoline polymer; a phenol-based
antioxidant such as
pentaerythritol-tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)pro-
pionate),
octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate,
1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene;
and a sulfur-based antioxidant such as
bis(2-methyl-4-(3-n-alkylthiopropionyloxy)-5-tert-butylphenyl)sulfide,
2-mercaptobenzimidazole and zinc salts thereof, and
pentaerythritol-tetrakis(3-lauryl-thiopropionate). An antioxidant
is preferably included in a content of 0.1 to 15.0 parts by mass,
and more preferably included in a content of 0.1 to 10 parts by
mass, with respect to 100 parts by mass of the resin.
[0138] Examples of the lubricant may include hydrocarbon-based,
siloxane-based, fatty-acid-based, fatty-acid-amide-based,
ester-based, alcohol-based, or metal-soap-based lubricants. These
lubricants are preferably added to the carrier resin.
[0139] Examples of the metal inactivator may include
N,N'-bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hydrazine,
3-(N-salicyloyl)amino-1,2,4-triazole, and
2,2'-oxamidebis(ethyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate).
[0140] As the filler (including a flame-retardant agent
(assistant)), a filler other than the above-mentioned various
fillers can be mentioned.
[0141] Next, the production method of the present invention is
specifically described.
[0142] In the production method of the present invention, in the
step (a), the organic peroxide of from 0.01 to 0.6 parts by mass,
the inorganic filler of from 10 to 400 parts by mass, the silane
coupling agent of from 1 to 15.0 parts by mass and the silanol
condensation catalyst, with respect to 100 parts by mass of the
base resin (R.sub.B) containing the non-aromatic organic oil at
least from 5 to 40 mass %, are melt-mixed to prepare a mixture. In
this manner, the silane master batch is prepared.
[0143] The mixing amount of the organic peroxide is within the
range of 0.01 to 0.6 parts by mass, and preferably 0.1 to 0.5 parts
by mass, with respect to 100 parts by mass of the base resin
(R.sub.B). When the mixing amount of the organic peroxide is too
low, the crosslinking reaction cannot progress during crosslinking
and the silane coupling agents can be condensed with each other,
and heat resistance, mechanical strength, and reinforcement
performance cannot be sufficiently obtained in some cases. On the
other hand, when the mixing amount of the organic peroxide is too
high, too many of the resin components can be directly crosslinked
with each other by a side reaction, and thus aggregated substances
can be generated. In other words, polymerization can be performed
in a suitable range by adjusting the mixing amount of the organic
peroxide within this range, and the composition that is excellent
in extrusion performance can be obtained without generating a
gel-like aggregated substance.
[0144] The mixing amount of the inorganic filler is from 10 to 400
parts by mass, preferably from 30 to 280 parts by mass, with
respect to 100 parts by mass of the base resin (R.sub.B). In the
case where the mixing amount of the inorganic filler is too small,
the grafting reaction of the silane coupling agent can be
non-uniformly made, and thus the desired heat resistance cannot be
obtained, or the appearance can be deteriorated due to the
non-uniform reaction. On the other hand, in the case where the
mixing amount is too large, since the load at the time of molding
or kneading can become very high, a secondary molding can be
difficult.
[0145] The mixing amount of the silane coupling agent is from 1 to
15.0 parts by mass, preferably more than 4 parts by mass and 15.0
parts by mass or less, and more preferably from 6 to 15.0 parts by
mass, with respect to 100 parts by mass of the base resin
(R.sub.B).
[0146] When the mixing amount of the silane coupling agent is too
low, the crosslinking reaction does not sufficiently progress, and
excellent flame resistance cannot be developed in some cases. On
the other hand, when the mixing amount is too high, the silane
coupling agent cannot be wholly adsorbed on the surface of the
inorganic filler, and the silane coupling agent can be volatilized
during kneading, which is not economical. In addition, the silane
coupling agent that is not adsorbed thereon can be condensed, and
the aggregated substance or burning/scorch can be caused on the
molded body, and the appearance can be deteriorated.
[0147] When the mixing amount of the silane coupling agent is more
than 4.0 parts by mass and 15.0 parts by mass or less, the
appearance is excellent. Details of a mechanism thereof are unknown
yet, but are presumed as described below. Specifically, in the step
(a), with regard to the reactions caused by organic peroxide
decomposition at the time of silane grafting of the silane coupling
agent onto the resin component, the grafting reaction having a high
reaction rate among the grafting reactions between the silane
coupling agents and the resin components, and the condensation
reaction between the silane coupling agents become dominant.
Accordingly, the crosslinking reaction between the resin
components, particularly between the polyolefin resins, which
causes appearance roughness or appearance aggregated substance, are
not likely to occur. Thus, the crosslinking reaction between the
resin components can be effectively suppressed depending on the
mixing amount of the silane coupling agent. Thus, the appearance
during molding is improved. In addition, the above-described defect
caused by the crosslinking reaction between the resin components is
minimized, and therefore it becomes difficult to cause poor
appearance even if the extruder is stopped and then the operation
is resumed. Thus, the silane crosslinked resin molded body having
favorable appearance can be produced with suppressing the
crosslinking reaction between the resin components.
[0148] Meanwhile, in the step (a), a large amount of the silane
coupling agent is bonded or adsorbed on the inorganic filler and
immobilized thereon. Accordingly, the condensation reaction between
the silane coupling agents that are bonded or adsorbed on the
inorganic filler is difficult to occur. In addition, the
condensation reaction between free silane coupling agents that are
not bonded or adsorbed on the inorganic filler is rarely caused
either, and generation of the gel-like aggregated substance caused
by the condensation reaction between the free silane coupling
agents can be suppressed.
[0149] Thus, it is considered that both of the crosslinking
reaction between the resin components and the condensation reaction
between the silane coupling agents can be suppressed by using a
specific amount of the silane coupling agent, and the silane
crosslinked resin molded body having clean appearance can be
produced.
[0150] In the production method of the present invention, the step
(a) includes "aspect in which the total amount of the base resin
(R.sub.B), namely 100 parts by mass, is incorporated" and "aspect
in which part of the base resin (R.sub.B) is incorporated" for the
base resin (R.sub.B). Accordingly, in the production method of the
present invention, 100 parts by mass of the base resin (R.sub.B)
only need to be contained in the mixture to be obtained in the step
(a), and the total amount of the base resin (R.sub.B) may be mixed
in the step (1) as mentioned later, or the part thereof is mixed in
the step (1) and a remainder may be mixed as the carrier resin in
step (2) as mentioned later, that is, the base resin (R.sub.B) may
be mixed in both steps, the step (1) and the step (2).
[0151] In the case where part of the base resin (R.sub.B) is
incorporated in the step (2), the mixing amount of 100 parts by
mass of the base resin (R.sub.B) in the step (a) is the total
amount of the base resin (R.sub.B) to be mixed in the step (1) and
the step (2).
[0152] Here, in the case where the remainder of the base resin
(R.sub.B) is incorporated in the step (2), the base resin (R.sub.B)
is incorporated in the step (1), preferably from 80 to 99 parts by
mass, and further preferably from 94 to 98 parts by mass, and in
the step (2), preferably from 1 to 20 parts by mass, and further
preferably from 2 to 6 parts by mass.
[0153] This step (a) includes at least the step (1) and the step
(3), and in a specific case, has at least the step (1) to the step
(3). When the step (a) has at least these steps, the components can
be uniformly melt-mixed, and an expected effect can be
obtained.
[0154] Step (1): Step of melt-mixing all or part of the base resin
(R.sub.B), the organic peroxide, the inorganic filler, and the
silane coupling agent, at a temperature equal to or higher than the
decomposition temperature of the organic peroxide, to prepare a
silane master batch,
[0155] Step (2): Step of melt-mixing a remainder of the base resin
(R.sub.B) and the silanol condensation catalyst, to prepare a
catalyst master batch, and
[0156] Step (3): Step of mixing the silane master batch and either
the silanol condensation catalyst or the catalyst master batch.
[0157] In the step (1), the base resin (R.sub.B), the organic
peroxide, the inorganic filler, and the silane coupling agent are
placed in a mixer, and the resultant mixture is melt-kneaded while
heated to the temperature equal to or higher than the decomposition
temperature of the organic peroxide, to prepare the silane master
batch.
[0158] In the step (1), the kneading temperature at which the
above-mentioned components are melt-blended is a temperature equal
to or higher than the decomposition temperature of the organic
peroxide, and preferably a temperature of the decomposition
temperature of the organic peroxide+25.degree. C. to 110.degree. C.
The decomposition temperature is preferably set after melting the
resin component. In addition, the kneading conditions, such as a
kneading time may be appropriately determined. If the kneading is
performed at a temperature lower than the decomposition temperature
of the organic peroxide, the grafting reaction of the silane
coupling agent and the like reaction do not occur, and thus, a
desired heat resistance cannot be obtained, and also the organic
peroxide can react during the extrusion, and thus, molding into a
desired shape cannot be conducted.
[0159] As a kneading method, a method that is generally used with
rubber and plastic can be satisfactorily used, and a kneading
device may be appropriately selected depending on the mixing amount
of the inorganic filler. As a kneading device, a single-screw
extruder, a twin-screw extruder, a roll, a Banbury mixer, or
various kneaders may be used, and an enclosed mixer such as Banbury
mixer or various kneaders is preferable from the standpoint of the
dispersibility of the resin component and the stability of the
crosslinking reaction.
[0160] In addition, when the inorganic filler is blended exceeding
100 parts by mass with respect to 100 parts by mass of the resin,
the kneading is generally performed with a continuous kneader, a
pressured kneader, or a Banbury mixer.
[0161] In the present invention, the phrase "all or part of the
base resin (R.sub.B), the organic peroxide, the inorganic filler,
and the silane coupling agent are melt-mixed" does not specify the
mixing order at the time of melt-mixing, and means that mixing may
be made in any order. In other words, the mixing order in the step
(1) is not particularly limited.
[0162] In addition, a method of mixing the base resin (R.sub.B) is
not particularly limited, either. For example, a base resin
(R.sub.B) that is premixed and prepared may be used, or each
component, for example, the resin component and the oil component
may be separately used, respectively.
[0163] In the step (1), for example, the base resin (R.sub.B), the
organic peroxide, the inorganic filler, and the silane coupling
agent can be melt-mixed at one time.
[0164] It is preferable that the silane coupling agent be not
introduced alone into the silane master batch, but be premixed with
the inorganic filler, or the like, and then introduced therein. In
this manner, it makes it difficult for the silane coupling agent to
volatilize during kneading, and it is possible to prevent the
condensation among that the silane coupling agents that are not
adsorbed on the inorganic fillers, which makes melt-blending
difficult. In addition, a desired shape can be obtained upon
extrusion molding.
[0165] As such a mixing method, preferred is a method of mixing or
dispersing an organic peroxide, an inorganic filler, and a silane
coupling agent, at a temperature less than the decomposition
temperature of the organic peroxide by using a mixer-type kneader
such as a Banbury mixer and a kneader, and then melt-mixing the
resultant mixture with the base resin (R.sub.B). In this manner, an
excessive crosslinking reaction between the resin components can be
prevented, and excellent appearance can be obtained.
[0166] The inorganic filler, the silane coupling agent, and the
organic peroxide are mixed at a temperature less than the
decomposition temperature of the organic peroxide, and preferably
at room temperature (25.degree. C.). A method of mixing the
inorganic filler, the silane coupling agent, and the organic
peroxide is not particularly limited, and the organic peroxide may
be simultaneously mixed with the inorganic filler or the like, or
may also be mixed in any of stages of mixing the silane coupling
agent with the inorganic filler. Specific examples of the method of
mixing the inorganic filler, the silane coupling agent, and the
organic peroxide include mixing methods such as wet treatment and
dry treatment.
[0167] Specific examples of the method of mixing the silane
coupling agent with the inorganic filler include a wet treatment in
which the silane coupling agent is added to the inorganic filler
being in a state dispersed in a solvent such as alcohol and water;
a dry treatment in which both are added and mixed under heating or
non-heating; and both of these methods. In the present invention, a
dry treatment is preferable in which the silane coupling agent is
added to the inorganic filler, preferably a dried inorganic filler,
and mixed under heating or non-heating.
[0168] In the above-mentioned wet mixing, it becomes easy for the
silane coupling agent to form a strong chemical bond with the
inorganic filler, and therefore a subsequent silanol condensation
reaction is less likely to proceed sometimes. On the other hand, in
the dry mixing, bonding of the silane coupling agent and the
inorganic filler is comparatively weak, and therefore it becomes
easy for the silanol condensation reaction to progress
effectively.
[0169] The silane coupling agent, added to the inorganic filler, is
present surrounding the surface of the inorganic filler; and a part
or whole thereof may be absorbed onto the inorganic filler or may
be chemically bonded to the surface of the inorganic filler. In
this state, it makes it possible to significantly suppress the
volatilization of the silane coupling agent during kneading with a
kneader or a Banbury mixer. In addition, it is considered that the
unsaturated group of the silane coupling agent is reacted with the
resin component by the added organic peroxide. Further, it is
considered that during molding, the silane coupling agents are
condensed by the silanol condensation catalyst. The mechanism of
this reaction is unknown, but it is considered that, at the time of
the condensation reaction, when bonding of the silane coupling
agent with the inorganic filler is too strong, the silane coupling
agent bonded with the inorganic filler is not freed therefrom even
if the silanol condensation catalyst is added thereto, and it
becomes difficult for the silanol condensation reaction
(crosslinking reaction) to progress.
[0170] In the step (1), the organic peroxide may be dispersed into
the inorganic filler after being mixed with the silane coupling
agent, or may be separately dispersed into the inorganic filler
separated from the silane coupling agent. In the present invention,
it is preferable that the organic peroxide and the silane coupling
agent be substantially simultaneously mixed.
[0171] In the present invention, only the silane coupling agent may
be mixed with the inorganic filler, and subsequently the organic
peroxide may be added thereto, depending on production conditions.
In other words, in the step (1), inorganic filler preliminarily
mixed with the silane coupling agent can be used. As a method of
adding the organic peroxide thereto, one in which the peroxide is
dispersed into other components, or the peroxide alone may be added
thereto.
[0172] In a preferable mixing method, subsequently, the mixture of
the inorganic filler, the silane coupling agent, and the organic
peroxide is melt-kneaded with the base resin (R.sub.B), while
performing heating at a temperature equal to or higher than the
decomposition temperature of the organic peroxide, to prepare a
silane master batch.
[0173] In the step (1), no silanol condensation catalyst is used.
In other words, in the step (1), the above-mentioned each component
is kneaded without substantially mixing the silanol condensation
catalyst. Thus, melt-mixing is easily conducted without causing
condensation of the silane coupling agents, and a desired shape can
be obtained at the time of extrusion molding. Here, the term
"without substantially mixing" means that the silanol condensation
catalyst unavoidably existing therein is not excluded, and may
exist at a degree at which the above-mentioned problem due to
silanol condensation of the silane coupling agent is not caused.
For example, in the step (1), the silanol condensation catalyst may
exist when the content is 0.01 parts by mass or less, with respect
to 100 parts by mass of the base resin (R.sub.B).
[0174] As described above, the step (1) is carried out, and the
silane master batch is prepared.
[0175] The silane master batch (also referred to as a silane MB) to
be prepared in the step (1) is used for producing a mixture
(heat-resistant silane crosslinkable resin composition) to be
prepared in the step (a), as mentioned later, preferably with the
silanol condensation catalyst or a catalyst master batch as
mentioned later. This silane MB is a mixture to be prepared by
melt-mixing the above-described components according to the step
(1).
[0176] The silane master batch prepared in the step (1) contains a
decomposed product of the organic peroxide, a reaction mixture of
the resin component, the inorganic filler and the silane coupling
agent, and the non-aromatic organic oil, and contains two kinds of
the silane crosslinkable resins (silane grafted polymers) in which
the silane coupling agents are grafted onto the resin components at
a degree at which molding can be made in the step (b) mentioned
later.
[0177] In the production method of the present invention,
subsequently, when the part of the base resin (R.sub.B) is
melt-mixed in the step (1), the step (2) is carried out in which
the remainder of the base resin (R.sub.B) and the silanol
condensation catalyst are melt-mixed, to prepare a catalyst master
batch. Accordingly, in the case where all of the base resin
(R.sub.B) is melt-mixed in the step (1), the step (2) may not be
carried out, or other resins as mentioned later may be used.
[0178] A mixing ratio of the base resin (R.sub.B) and the silanol
condensation catalyst in the step (2) is set so as to satisfy a
mixing ratio of the base resin (R.sub.B) in the silane master batch
in the step (3) as mentioned later. The base resin (R.sub.B) may be
mixed, as the carrier resin, with the silanol condensation
catalyst, and the remainder of the base resin (R.sub.B) mixed in
the step (1) may be used.
[0179] Mixing of the silanol condensation catalyst with the base
resin (R.sub.B) is appropriately determined according to a melting
temperature of the base resin (R.sub.B). For example, the kneading
temperature is preferably applied from 80 to 250.degree. C., and
further preferably from 100 to 240.degree. C. Kneading conditions
such as a kneading time can be appropriately set. A kneading method
can be carried out in a manner similar to the above-described
kneading method.
[0180] With the silanol condensation catalyst, any other carrier
resin may be mixed in addition to or in place of the remainder of
the base resin (R.sub.B). In other words, the catalyst master batch
may be prepared in the step (2) by melt-mixing the silanol
condensation catalyst with the remainder of the base resin
(R.sub.B) in the case of melt-mixing of the part of the base resin
(R.sub.B) in the step (1) or with a resin other than the resin
component used in the step (1). Other carrier resins are not
particularly limited, and various resins can be used.
[0181] When the carrier resin is any other resin, in view of
capability of rapidly promoting silane crosslinking and difficulty
in generating the aggregated substance during molding in the step
(b), an amount of incorporating any other resin thereinto is
preferably from 1 to 60 parts by mass, further preferably from 2 to
50 parts by mass, and still further preferably from 2 to 40 parts
by mass, with respect to 100 parts by mass of the base resin
(R.sub.B).
[0182] In addition, a filler may be added or may not to be added to
this carrier resin. A filler amount on the above occasion is not
particularly limited, but is preferably 350 parts by mass or less
with respect to 100 parts by mass of the carrier resin. The reason
is that, when the filler amount is too large, it is difficult for
the silanol condensation catalyst to disperse, and thereby
rendering progress of crosslinking difficult. On the other hand,
when the amount of the carrier resin is too large, a degree of
crosslinking in the molded body is reduced, and it is possible that
proper heat resistance cannot be obtained.
[0183] The thus prepared catalyst master batch is a mixture of the
silanol condensation catalyst and the carrier resin, and the filler
to be added if desired.
[0184] The thus catalyst master batch (also referred to as a
catalyst MB) is used, together with the silane MB, for production
of the heat-resistant silane crosslinkable resin composition to be
prepared in the step (a).
[0185] In the production method of the present invention,
subsequently, the step (3) of obtaining a mixture by mixing the
silane master batch and either the silanol condensation catalyst or
the catalyst master batch prepared in the step (2), is carried
out.
[0186] As the mixing method, any mixing method may be applied, as
long as a uniform mixture can be obtained as mentioned above. For
example, pellets may be blended with each other at ordinary
temperature or a high temperature, such as dry blend, and then
placed in a molding machine, or the pellets may be blended, and
then melt-mixed, re-pelletized, and then placed in a molding
machine.
[0187] In any mode of mixing, in order to avoid the silanol
condensation reaction, it is preferable that the silane master
batch and the silanol condensation catalyst are not kept in a high
temperature state for a long period of time in the state of being
mixed. The mixture to be obtained is taken as a mixture in which at
least moldability in molding in the step (b) is kept.
[0188] The amount of incorporating the silanol condensation
catalyst is preferably from 0.0001 to 0.7 parts by mass, and
further preferably from 0.001 to 0.5 parts by mass, with respect to
100 parts by mass of the base resin (R.sub.B). When the mixing
amount of the silanol condensation catalyst is within the
above-mentioned range, the crosslinking reaction by the
condensation reaction of the silane coupling agent easily
progresses substantially uniformly, and heat resistance,
appearance, and physical properties of the heat-resistant silane
crosslinked resin molded body are excellent, and productivity is
also improved.
[0189] When crosslinking treatment is conducted without employing
warm water treatment or the like in the step (c) as mentioned
later, the amount of incorporation is preferably from 0.05 to 0.5
parts by mass, and further preferably 0.1 parts by mass or more in
order to develop excellent heat resistance immediately after
extrusion. When 0.1 parts by mass or more of the silanol
condensation catalyst is added thereto, it may cause a reaction in
the molding machine and the appearance can be deteriorated in some
cases. However, according to an effect of appearance improvement by
addition of the non-aromatic organic oil thereto, a problem of
deterioration of appearance does not occur even upon adding 0.1
parts by mass or more of the catalyst thereto, and excellent heat
resistance can be obtained immediately after extrusion.
[0190] In the step (b), mixing conditions of the silane master
batch with the silanol condensation catalyst or the catalyst master
batch are appropriately selected. In other words, when the silanol
condensation catalyst alone is mixed with the silane master batch,
the mixing conditions are set to appropriate melt-mixing conditions
according to the resin component.
[0191] On the other hand, when the catalyst master batch containing
the silanol condensation catalyst is mixed with the silane master
batch, melt-mixing is preferable in view of dispersion of the
silanol condensation catalyst, and is basically similar to the
melt-mixing in the step (1). There are resin components whose
melting points cannot be measured by DSC or the like, elastomers
for example, but kneading is performed at a temperature at which at
least any of the resin component and the organic peroxide melts.
The melting temperature is appropriately selected according to the
melting temperature of the carrier resin, and it is preferably from
80 to 250.degree. C., and more preferably from 100 to 240.degree.
C. In addition, the kneading conditions such as a kneading time may
be appropriately set.
[0192] This step (3) only needs to be a step in which the silane
master batch and the silanol condensation catalyst (C) are mixed,
to obtain a mixture, and is preferably a step in which the catalyst
master batch containing the silanol condensation catalyst (C) and
the carrier resin is melt-mixed with the silane master batch.
[0193] As described above, the step (a), in other words, the method
of producing a heat-resistant silane crosslinkable resin
composition of the present invention, is carried out, and as
mentioned later, a heat-resistant silane crosslinkable resin
composition containing at least two kinds of silane crosslinkable
resins in which the crosslinking methods are different, is
produced. Accordingly, the heat-resistant silane crosslinkable
resin composition of the present invention is a composition
obtained by carrying out the step (a), and is considered as an
admixture of the silane master batch and either the silanol
condensation catalyst or the catalyst master batch. The components
are basically the same with the silane master batch and the silanol
condensation catalyst or the catalyst master batch.
[0194] As described above, the silane MB, and the silanol
condensation catalyst or the catalyst master batch can be used as a
batch set for producing a heat-resistant silane crosslinkable resin
composition.
[0195] In the method of producing a heat-resistant silane
crosslinked resin molded body of the present invention,
subsequently, the step (b) and (c) are carried out. In other words,
in the method of producing a heat-resistant silane crosslinked
resin molded body of the present invention, the step (b) of
obtaining a molded body by molding the mixture thus obtained,
namely, the heat-resistant silane crosslinkable resin composition
of the present invention, is performed. The step (b) only has to
mold the mixture, and the molding method and molding conditions can
be appropriately selected depending on the form of the
heat-resistant product of the present invention. For example,
extrusion molding or the like is selected in a case where the
heat-resistant product of the present invention is an electric wire
or an optical fiber cable.
[0196] In the step (b), when the mixing amount of the silane
coupling agent exceeds 4 parts by mass, the operation of the
extruder can also be resumed without reducing excellent appearance
of the molded body after the extruder is once stopped due to an
event such as cleaning of the extruder, changing of set-ups,
adjusting of decentering or suspension of production.
[0197] In addition, the step (b) can be carried out simultaneously
or continuously with the step (3) in the step (a). For example, a
series of steps can be employed in which the silane master batch
and either the silanol condensation catalyst or the catalyst master
batch are melt-kneaded in a coating device, and subsequently, for
example, extruded and coated on an electric wire or fiber, and
molded into a desired shape.
[0198] As described above, the heat-resistant silane crosslinkable
resin composition of the present invention is molded, but the
molded body of the heat-resistant silane crosslinkable resin
composition to be obtained in the step (a) and the step (b) is a
non-crosslinked body. Accordingly, a heat-resistant silane
crosslinked resin molded body of the present invention is a
crosslinked or finally crosslinked molded body formed by carrying
out the following step (c) after the step (a) and the step (b).
[0199] In the method of producing the heat-resistant silane
crosslinked resin molded body of the present invention, a step is
carried out in which the molded body (non-crosslinked body)
obtained in the step (b) is contacted with water. Thus, the
hydrolyzable group of the silane coupling agent is hydrolyzed into
silanol, hydroxyl groups in the silanol are condensed with each
other by the silanol condensation catalyst existing in the resin,
and the crosslinking reaction occurs, and the heat-resistant silane
crosslinked resin molded body in which the molded body is
crosslinked can be obtained. The treatment itself in this step (c)
can be carried out according to an ordinary method. The
hydrolyzable groups in the silane coupling agent are hydrolyzed by
contacting moisture with the molded body, and the silane coupling
agents are condensed with each other to form a crosslinked
structure.
[0200] The condensation reaction between the silane coupling agents
progresses just in storage at ordinary temperature. Accordingly, in
the step (c), it is unnecessary to positively bring the molded body
(non-crosslinked body) with water. In order to further accelerate
crosslinking, the molded body can also be contacted with moisture.
For example, the method of positively contacting the molded body
with water can be employed, such as immersion into warm water,
placement in a wet heat bath, and exposure to high temperature
water vapor. In addition, pressure may be applied in order to
penetrate moisture thereinto on the above occasion.
[0201] As described above, the method of producing the
heat-resistant silane crosslinked resin molded body of the present
invention is carried out, and the heat-resistant silane crosslinked
resin molded body is produced from the heat-resistant silane
crosslinkable resin composition of the present invention.
Accordingly, the heat-resistant silane crosslinked resin molded
body of the present invention is a molded body obtained by carrying
out the step (a) to the step (c).
[0202] Details of a reaction mechanism in the production method of
the present invention are unknown yet, but it is considered as
described below. Specifically, when the resin component is
heat-kneaded with the inorganic filler and the silane coupling
agent, in the presence of the organic peroxide, at a temperature
equal to or higher than the decomposition temperature of the
organic peroxide, the organic peroxide is decomposed to generate
radical, and grafting onto the resin component is caused by the
silane coupling agent. In addition, a reaction of forming a
chemical bond due to covalent bonding of the silane coupling agent
with the group such as the hydroxyl group on the surface of the
inorganic filler also partially occurs by heating on the above
occasion.
[0203] In the present invention, the final crosslinking reaction is
performed in the step (c), and owing thereto, when the silane
coupling agent is incorporated into the resin in a specific amount
as mentioned above, the inorganic filer can be incorporated
thereinto in a large amount without adversely affecting extrusion
processability during molding, and the molded body can
simultaneously have the heat resistance, the mechanical
characteristics and the like while ensuring the excellent flame
retardancy.
[0204] In addition, a mechanism of operation in the above-described
process of the present invention is unknown yet, but it is assumed
as described below. Specifically, by using the inorganic filler and
the silane coupling agent before kneading and/or during kneading
with the base resin (R.sub.B), the silane coupling agent is bonded
with the inorganic filler by means of the alkoxy group and is
bonded with a non-crosslinked part in the resin component by means
of the ethylenically unsaturated group, such as vinyl group,
existing at another end, or is physically and chemically adsorbed
onto pores or the surface of the inorganic filler, and kept
thereon, without being bonded with the inorganic filler. Thus, the
present invention can form a silane coupling agent bonded with the
inorganic filler by strong bonding (as the reason therefor, for
example, formation of chemical bond with hydroxyl group or the like
on the surface of the inorganic filler is considered), and a silane
coupling agent bonded therewith by weak bonding (as the reason
therefor, for example, interaction due to hydrogen bond,
interaction between ions, partial electric charges, or dipoles,
action due to adsorption, or the like is considered). In this
state, if the organic peroxide is added thereto and kneading is
performed, at least two kinds of silane crosslinkable resins are
formed in which the silane coupling agents having different
bondings with the inorganic filler are graft reacted onto the resin
component, without hardly causing volatilization of the silane
coupling agent, as mentioned later.
[0205] By the above kneading, among the silane coupling agents, the
silane coupling agent having strong bonding with the inorganic
filler keeps the bonding with the inorganic filler, and the
crosslinkable group such as ethylenically unsaturated group is
subjected to the grafting reaction onto a crosslinkable site in the
resin component. In particular, when a plurality of the silane
coupling agents are bonded on the surface of one inorganic filler
particle through strong bonding, a plurality of the resin
components are bonded through the inorganic filler particle. By
these reactions or bondings, a crosslinked network through the
inorganic filler spreads. In other words, a silane crosslinkable
resin is formed in which the silane coupling agents bonded with the
inorganic filler is graft reacted onto the resin component.
[0206] In the case of the silane coupling agent having strong
bonding with the inorganic filler, the condensation reaction due to
silanol condensation catalyst in the presence of water hardly
occurs, and bonding with the inorganic filler is kept. Thus, the
bonding of the inorganic filler with the resin component is formed,
and crosslinking of the resin components through the silane
coupling agent is caused. By this, adhesion between the resin
component and the inorganic filler is consolidated, and the molded
body that is excellent in mechanical strength and abrasion
resistance and hard to be scratched is obtained.
[0207] On the other hand, among the silane coupling agents, the
silane coupling agent having weak bonding with the inorganic filler
is released from the surface of the inorganic filler, and the
crosslinkable group of the silane coupling agent, such as the
ethylenically unsaturated group or the like, reacts with the
radical of the resin component as generated by hydrogen radical
abstraction caused by the radical generated by decomposition of the
organic peroxide, and the grafting reaction occurs. In other words,
the silane crosslinkable resin is formed in which the silane
coupling agent released from the inorganic filler is graft reacted
onto the resin component. The silane coupling agent in the
thus-formed grafted part is mixed with the silanol condensation
catalyst afterward, and contacted with moisture to cause the
crosslinking reaction by the condensation reaction.
[0208] In particular, in the present invention, the crosslinking
reaction due to the condensation reaction using the silanol
condensation catalyst in the presence of water in the step (c) is
performed after the molded body is formed. Thus, workability in the
steps up to forming the molded body is superb, and higher heat
resistance than ever before can be obtained, in comparison with a
conventional method that forms a molded body after the final
crosslinking reaction. In addition, a plurality of the silane
coupling agents can be bonded on the surface of one inorganic
filler particle, and high mechanical strength can be obtained.
[0209] As described above, it is considered that the silane
coupling agent bonded with the inorganic filler by strong bonding
contributes to high mechanical characteristics, and depending on
circumstances, to abrasion resistance, scratch resistance or the
like. Further, it is considered that the silane coupling agent
bonded with the inorganic filler by weak bonding contributes to
improvement of a degree of crosslinking, in other words,
improvement of the heat resistance.
[0210] In the present invention, in particular, generation of the
aggregated substance is significantly suppressed even when the
molded body is produced under conditions in which the aggregated
substance is easily generated, and the silane crosslinked resin
molded body having excellent appearance can be produced. In other
words, when the step (a) at least having the above-described steps
(1) and (3) is carried out by using the base resin (R.sub.B)
containing the non-aromatic organic oil of from 5 to 40 parts by
mass, local heat generation during melt-kneading in the step (a),
particularly in the step (1), is suppressed, and generation of the
aggregated substance can be significantly reduced. Further, when
the step (a) is carried out with using the base resin (R.sub.B)
containing the non-aromatic organic oil, a hydrolysis reaction of
the silane coupling agent before molding can be suppressed by
preventing moisture from being mixed or also incorporated thereinto
from outside during melt-kneading and during storage of a
melt-blended product, and the non-aromatic organic oil functions as
an appearance improver during molding, and the appearance of the
molded body can be significantly improved.
[0211] A mechanism for this point is unknown yet, but it is assumed
as described below.
[0212] Specifically, causes of deteriorated appearance of the
heat-resistant silane crosslinked resin molded body are considered
to be a silane crosslinked aggregated substance due to local silane
crosslinking and poor flowability due to crosslinking of the resin
components with each other.
[0213] It is considered that the silane crosslinked aggregated
substance is generated as described below. Specifically, not only
the silane grafting reaction, but also a polymerization reaction
between the resin components, the condensation reaction between the
silane coupling agents, and the like occur for reasons such as
locally increased heating temperature of the melt-kneaded product
and a localized crosslinking agent (silane coupling agent) during
the silane grafting reaction. A substance having a larger molecular
weight in comparison with others is locally produced by these
reactions. This substance having the larger molecular weight is
more significantly produced as the melt-kneading temperature
increases, and furthermore is not melted even during molding, and
formed into the gel-like aggregated substance. This substance
causes poor appearance.
[0214] However, in the present invention, it is considered that
generation of the above-described event (the polymerization
reaction, the condensation reaction and the like) that may occur
during melt-kneading can be suppressed and generation of the silane
crosslinked aggregated substance is significantly reduced by
performing specific melt-kneading by using the base resin (R.sub.B)
containing a specific amount of the non-aromatic organic oil.
[0215] In addition, it is considered that the poor flowability due
to crosslinking of the resin components with each other is caused
by occurrence of the condensation reaction of the silane coupling
agent in an earlier stage. This event may be caused by occurrence
of the hydrolysis reaction of the silanol group when moisture is
mixed for any reason after the silane grafting reaction. Even when
the silanol group is hydrolyzed, no condensation reaction occurs
under ordinal temperature, and therefore there exists no problem.
However, when kneading and molding are performed together with the
silanol condensation catalyst at a high temperature at the time of
molding, the silanol condensation reaction occurs, and the silane
coupling agents are crosslinked by the condensation reaction during
molding in some cases. Mixing of moisture may be ordinarily caused
not in a special condition, for example, under a high temperature
and high humidity. "Crosslinking" means a pseudo-state in which the
molecular weight is infinitely large, but in the above-described
crosslinking, the molecular weight becomes large, although the
molecular weight is not infinitely large. When the molecular weight
becomes large, flowability is generally deteriorated, and
moldability, particularly high-speed moldability is
deteriorated.
[0216] However, in the present invention, by performing specific
melt-kneading with using the base resin (R.sub.B) containing the
specific amount of the non-aromatic organic oil, mixing of
excessive moisture from outside can be blocked to prevent the
hydrolysis reaction of the silanol group before molding. In
addition, the flowability can be improved by minimizing the
molecular weight of the crosslinked product by the above-described
silanol condensation reaction.
[0217] Thus, it is considered that the appearance of the molded
body can be improved.
[0218] Furthermore, in the present invention, when more than 4.0
parts by mass and 15.0 parts by mass or less of the silane coupling
agent are mixed with the inorganic filler, as mentioned above, the
crosslinking reaction between the resin components during
melt-kneading in the step (a), especially in the step (1), can be
effectively suppressed. In addition, the silane coupling agent is
bonded with the inorganic filler, and is hard to volatilize even
during melt-kneading in the step (a), especially in the step (1),
and the reaction between the free silane coupling agents can also
be effectively suppressed. Accordingly, it is considered that, even
if the extruder is stopped and then the operation is resumed, it is
hard to cause poor appearance, and a silane crosslinked resin
molded body having a favorable appearance can be produced.
[0219] Here, the term "once stopped and then the operation is
resumed" means, although conditions are influenced by the
composition of the base resin (R.sub.B), processing conditions or
the like, and cannot be unequivocally mentioned, for example, the
extruder can be stopped for up to 5 minutes, preferably up to 10
minutes, and further preferably up to 15 minutes in terms of an
interval. Temperature at this time is not particularly limited, as
long as it is a temperature at which the resin component is
softened or melted, and is 200.degree. C., for example.
[0220] The production method of the present invention is applicable
to a production of a component part of or a member of a product
(including a semi-finished product, a part and a member), such as a
product requiring heat resistance or flame retardancy, a product
requiring strength, and a product using a rubber material. Specific
examples of such a heat-resistant product or a flame-retardant
product include an electric wire such as a heat-resistant
flame-retardant insulated wire, a heat-resistant flame-retardant
cable coating material, a rubber substitute wire and cable
material, other heat-resistant flame-retardant wire parts, a
flame-retardant heat-resistant sheet, and a flame-retardant
heat-resistant film. In addition, the production method is
applicable to production of a power supply plug, a connector, a
sleeve, a box, a tape base material, a tube, a sheet, a packing, a
cushion material, a seismic isolating material, a wiring material
used in internal and external wiring for electric and electronic
instruments, and particularly an electric wire or an optical fiber
cable. Among the above described component or the like of product,
the production method of the present invention is particularly
preferably applied to production of an insulator, a sheath, or the
like of electric wire and optical cable, and it can be formed as a
coating thereof.
[0221] The insulator, the sheath or the like can be molded into a
shape thereof by, for example, coating while melt-kneading is
performed in an extrusion coating device. These molded articles
such as insulators or sheaths may be produced by extrusion-coating
the high heat-resistant crosslinking composition that does not melt
at a high temperature and is added with the inorganic fillers in a
large amount, around a conductor or around a conductor that is
prepared by attaching tensile strength fiber in a length or
entwisting, using an extrusion coating device that is widely used,
without using a specific instrument such as an electron beam
crosslinking instrument. For example, as a conductor, any one such
as single-conductor or twisted-conductor of a soft copper may be
used. In addition, as a conductor, in addition to a naked
conductor, a tin-coated conductor or a conductor having an
enamel-coated insulating layer may be used. The thickness of the
insulating layer formed around the conductor (a coating layer
formed of the heat-resistant resin composition of the present
invention) is not particularly limited, and generally about 0.15 to
5 mm.
EXAMPLES
[0222] The present invention is described in more detail based on
examples given below, but the present invention is not limited by
the following examples. In addition, in Table 1 to Table 4, the
numerical values for incorporated amounts of the respective
Examples and Comparative Examples are in terms of part by mass.
[0223] Examples 1 to 43 and Comparative Examples 1 to 8 were
carried out by using the components shown in Table 1 to Table 4,
and changing specifications or manufacturing conditions or the
like, respectively, and the results of evaluation as mentioned
later were collectively shown.
[0224] The compound described below was used as each component
shown in Tables 1 to 4.
<Base resin (R.sub.B)>
(1) Resin Component
[0225] As the polyolefin resin,
Resin A: "UE320" (manufactured by Japan Polyethylene Corporation,
NOVATEC PE (trade name), linear low-density polyethylene (LLDPE),
density: 0.92 g/cm.sup.3) Resin B: "Evolue SP0540" (trade name,
manufactured by Prime Polymer Co., Ltd., linear metallocene
polyethylene (LLDPE), density: 0.90 g/cm.sup.3) Resin C: "ENGAGE
7256" (trade name, manufactured by Dow Chemical Japan Ltd., linear
low-density polyethylene (LLDPE), density: 0.885 g/cm.sup.3) Resin
D: "EV170" (trade name, manufactured by Du Pont-Mitsui Chemicals,
ethylene-vinyl acetate copolymer resin (EVA), the content of VA: 33
mass %, density: 0.96 g/cm.sup.3) Resin E: "NUC6510" (trade name,
manufactured by Nippon Unicar Co. Ltd., ethylene-ethyl acrylate
resin, the content of EA: 23 mass %, density: 0.93 g/cm.sup.3)
[0226] As the styrene-based elastomer,
"SEPTON 4077" (trade name, manufactured by Kuraray Co., Ltd., SEPS,
the content of styrene: 30 mass %)
[0227] As the ethylene rubber,
Ethylene rubber A: "EPT3045" (trade name, manufactured by Mitsui
Chemicals, Inc., ethylene-propylene-diene rubber, the content of
diene: 4.7 mass %, the content of ethylene: 56 mass %) Ethylene
rubber B: "EPT0045" (trade name, manufactured by Mitsui Chemicals,
Inc., ethylene-propylene rubber, the content of diene: 0 mass %,
the content of ethylene: 51 mass %)
(2) Oil Component
[0228] As the non-aromatic organic oil,
"COSMO NEUTRAL 500" (trade name, manufactured by COSMO OIL
LUBRICANTS CO., LTD., paraffin oil, aniline point: 109.1.degree.
C., average molecular weight: 521)
<Inorganic Filler>
[0229] Magnesium hydroxide 1: "KISUMA 5" (trade name, manufactured
by Kyowa Chemical Industry Co., Ltd., surface-untreated magnesium
hydroxide) Magnesium hydroxide 2: "KISUMA 5L" (trade name,
manufactured by Kyowa Chemical Industry Co., Ltd., magnesium
hydroxide pretreated with silane coupling agent, treatment amount 1
mass %) Aluminum hydroxide: "Higilite 42M" (trade name,
manufactured by SHOWA DENKO K.K., surface-untreated aluminum
hydroxide) Calcium carbonate: "SOFTON 1200" (trade name,
manufactured by SHIRAISHI CALCIUM KAISHA, LTD., surface-untreated
calcium carbonate)
<Organic Peroxide>
[0230] "Perkadox BC-FF" (trade name, dicumyl peroxide (DCP) by
Kayaku Akzo Corporation, decomposition temperature: 149.degree.
C.)
<Silane Coupling Agent>
[0231] "KBM-1003" (trade name, manufactured by Shin-Etsu Chemical
Co., Ltd., vinyltrimethoxysilane)
<Silanol Condensation Catalyst>
[0232] "ADKSTAB OT-1" (trade name, manufactured by ADEKA
CORPORATION, dioctyltin dilaurate)
<Carrier Resin>
[0233] Above-mentioned "UE320" (trade name) {0124}
Examples 1 to 40 and Comparative Examples 1 to 8
[0234] In Examples and Comparative Examples, part of resin
components that compose a base resin (R.sub.B) was used as a
carrier resin of a catalyst master batch. Specifically, LLDPE
(UE320) (5 parts by mass), one of the resin components that compose
the base resin (R.sub.B), was used.
[0235] In the mass ratios shown in Tables 1 to 4, an organic
peroxide, an inorganic filler, and a silane coupling agent were
placed in a 10 L Henschel mixer manufactured by Toyo Seiki Kogyo
Co., Ltd., and then mixed at room temperature (25.degree. C.) for 1
hour in the mixer, to obtain a powder mixture.
[0236] Subsequently, in the mass ratios shown in Tables 1 to 4, the
powder mixture and resin components and an oil component shown in
Tables 1 to 4 were placed in a 2 L Banbury mixer manufactured by
Nippon Roll MFG Co., Ltd., and kneaded at a temperature equal to or
higher than the decomposition temperature of the organic peroxide,
specifically a temperature of 180.degree. C. to 190.degree. C., for
about 10 minutes at the revolution number of 35 rpm, and then
discharged at a material discharging temperature of 180 to
190.degree. C., to obtain a silane master batch (step (1)). The
silane MB obtained contains at least two kinds of silane
crosslinkable resins in which silane coupling agents were graft
reacted onto the resin components.
[0237] On the other hand, in the mass ratios shown in Tables 1 to
4, a carrier resin "UE320" and a silanol condensation catalyst were
separately melt-mixed at 180 to 190.degree. C. using a Banbury
mixer, and the resultant mixture was discharged at a material
discharging temperature of 180 to 190.degree. C., to obtain a
catalyst master batch (Step (2)). This catalyst master batch is a
mixture of the carrier resin and the silanol condensation
catalyst.
[0238] Subsequently, in the mass ratios shown in Tables 1 to 4,
that is, in the ratios to be 5 parts by mass of the carrier resin
in the catalyst MB with respect to 95 parts by mass of the base
resin (R.sub.B) in the silane MB, the silane MB and the catalyst MB
were melt-mixed using a Banbury mixer at 180.degree. C. (step
(3)).
[0239] The step (a) was conducted in this manner, and the
heat-resistant silane crosslinkable resin composition was prepared.
This heat-resistant silane crosslinkable resin composition is a
mixture of the silane MB and the catalyst MB, and contains at least
two kinds of the above-mentioned silane crosslinkable resins.
[0240] Subsequently, this heat-resistant silane crosslinkable resin
composition was placed in a 40 mm (screw diameter) extruder
(compression-zone screw temperature: 190.degree. C., head
temperature: 200.degree. C.) with L/D=24 (ratio of screw effective
length L to diameter D), and coated on an outside of a 1/0.8 TA
conductor at a 1 mm thickness, to obtain an electric wire
(non-crosslinked) having an outer diameter of 2.8 mm (step
(b)).
[0241] The thus-obtained electric wire (non-crosslinked) was
allowed to stand for 24 hours under an atmosphere of a temperature
of 80.degree. C. and a humidity of 95%, to perform a
polycondensation reaction of silanol (step (c)).
[0242] In this manner, an electric wire coated with the
heat-resistant silane crosslinked resin molded body was
manufactured.
[0243] This heat-resistant silane crosslinked resin molded body is,
as mentioned above, transformed into the above-mentioned silane
crosslinked resin in which the silane coupling agent in the silane
crosslinkable resin was converted into silanol, and hydroxyl groups
in the silanol were crosslinked with each other by the condensation
reaction.
Example 41
[0244] A silane MB and a catalyst MB were prepared (Step (1) and
Step (2)), respectively, in the same manner as the above-described
Example 1, except that each component shown in Table 4 was used in
the mass ratio (parts by mass) shown in the same Table.
[0245] Subsequently, the silane MB and the catalyst MB thus
obtained were placed in a closed-type ribbon blender, and
dry-blended at room temperature (25.degree. C.) for 5 minutes, to
obtain a dry-blended product. On the above occasion, a mixing ratio
of the silane MB to the catalyst MB was adjusted to a mass ratio
(see Table 4) to be 95 parts by mass of the base resin in the
silane MB to 5 parts by mass of the carrier resin in the catalyst
MB. Subsequently, this dry-blended product was placed in a 40 mm
extruder (compression zone screw temperature: 190.degree. C., head
temperature: 200.degree. C.) with L/D=24, and coated on the outside
of a 1/0.8 TA conductor at a 1 mm thickness while melt-blending was
performed in the extruder screw, to obtain an electric wire
(non-crosslinked) having an outer diameter of 2.8 mm (step (3) and
step (b)).
[0246] The thus-obtained electric wire (non-crosslinked) was
allowed to stand for 24 hours under an atmosphere of a temperature
of 80.degree. C. and a humidity of 95% (step (c)).
[0247] In this manner, an electric wire coated with the
heat-resistant silane crosslinked resin molded body was
manufactured.
Example 42
[0248] An electric wire (outer diameter: 2.8 mm, non-crosslinked)
in which a periphery of a conductor was coated with a
heat-resistant silane crosslinkable resin composition was obtained
(step (a) and step (b)) in the same manner as the above-described
Example 1, except that each component shown in Table 4 was used in
the mass ratio (parts by mass) shown in the same Table.
[0249] The thus-obtained electric wire was allowed to stand for 72
hours under an atmosphere of a temperature of 23.degree. C. and a
humidity of 50% (step (c)).
[0250] In this manner, an electric wire coated with the
heat-resistant silane crosslinked resin molded body was
manufactured.
Example 43
[0251] A silane MB was prepared (Step (1)) in the same manner as
the above-described Example 1, except that each component shown in
Table 4 was used in the mass ratio (parts by mass) shown in the
same Table.
[0252] On the other hand, in the mass ratios shown in Table 4, a
carrier resin "UE320" and a silanol condensation catalyst were
melt-mixed in a twin-screw extruder, to obtain a catalyst MB (Step
(2)). A screw diameter of the twin-screw extruder was 35 mm, and
cylinder temperature was set to 180 to 190.degree. C. The catalyst
MB obtained is a mixture of the carrier resin and the silanol
condensation catalyst.
[0253] Subsequently, the silane MB and the catalyst MB obtained
were melt-mixed using a Banbury mixer at 180.degree. C. (step (3)).
A mixing ratio of the silane MB to the catalyst MB was adjusted to
a mass ratio (see Table 4) to be 95 parts by mass of the base resin
in the silane MB to 5 parts by mass of the carrier resin in the
catalyst MB. In this manner, a heat-resistant silane crosslinkable
resin composition was prepared. This heat-resistant silane
crosslinkable resin composition is a mixture of the silane MB and
the catalyst MB, and contains at least two kinds of the
above-mentioned silane crosslinkable resins.
[0254] Subsequently, this heat-resistant silane crosslinkable resin
composition was placed in a 40 mm extruder (compression zone screw
temperature: 190.degree. C., head temperature: 200.degree. C.) with
L/D=24, and coated on an outside of 1/0.8 TA conductor at a 1 mm
thickness, to obtain an electric wire (non-crosslinked) having an
outer diameter of 2.8 mm (step (b)).
[0255] The electric wire (non-crosslinked) obtained was allowed to
stand in a state in which the wire was immersed into warm water
having a temperature of 50.degree. C. for 10 hours (step (c)).
[0256] In this manner, an electric wire having a coating formed of
the heat-resistant silane crosslinked resin molded body was
manufactured.
[0257] The electric wires thus manufactured were subjected to the
following evaluation, and the results thereof are shown in Tables 1
to 4.
<Mechanical Characteristics>
[0258] A tensile test was conducted to evaluate mechanical
characteristics of the electric wire.
[0259] This tensile test was conducted in accordance with JIS C
3005. The test was conducted at a gauge length of 25 mm and at a
tensile speed of 200 mm/min by using a tubular piece of an electric
wire prepared by removing a conductor from the electric wire, to
measure tensile strength (MPa) and tensile elongation
[0260] In an evaluation of the tensile strength, one having a
tensile strength of 10 MPa or more is taken as "A", one having a
tensile strength of 6.5 MPa or more and less than 10 MPa is taken
as "B", one having a tensile strength less than 6.5 MPa is taken as
"C", and "A" and "B" are acceptable levels.
[0261] In an evaluation of the tensile elongation, one having a
tensile elongation of 200% or more is taken as "A", one having a
tensile elongation of 125% or more and less than 200% is taken as
"B", and one having a tensile elongation less than 125% is taken as
"C", and "A" and "B" are acceptable levels.
<Heat Resistance Test 1>
[0262] As a heat resistance test 1, a test was conducted in
accordance with "heat deformation test" specified in JIS C
3005.
[0263] A load was adjusted to 5 N, and heating temperature was
adjusted to 160.degree. C.
[0264] In an evaluation, one having a deformation ratio of 40% or
less is taken as "A" (acceptable level), and one having a
deformation ratio of 40% or more is taken as "B".
<Heat Resistance Test 2>
[0265] As a heat resistance test 2, a hot set test was
conducted.
[0266] As the hot set test, a tubular piece of an electric wire was
prepared, a gauge line of 50 mm in length was added thereto, and
then after setting a pendulum of 20 N/cm.sup.2 to the tubular
piece, the tubular piece was left for 15 minutes in a constant
temperature chamber of 170.degree. C. Thereafter, the length after
being left was measured, to obtain elongation percentage.
[0267] In an evaluation, one having an elongation percentage of 50%
or less is taken as "A", one having a percentage of more than 50%
and 100% or less is taken as "B", and one having a percentage of
more than 100% is taken as "C", and "A" and "B" are acceptable
levels.
<Bleed Characteristics of Electric Wire>
[0268] A bleed test was conducted to evaluate bleed characteristics
of the electric wire.
[0269] As the bleed test, an electric wire produced was left for
one week under an atmosphere of 50.degree. C., and then a bleed
state on a surface of the electric wire was visually confirmed.
[0270] In an evaluation, one having bleed unconfirmable on the
surface of the electric wire is taken as "A", one having bleed
confirmable thereon but having no problem as a product is taken as
"B", and one having bleed clearly confirmable is taken as "C", and
"A" and "B" are a desirable level as products.
[0271] This bleed test is a reference test, and is not always
required to reach the desirable level.
<Extrusion Appearance Characteristics 1 of Electric Wire>
[0272] Extrusion appearance test 1 was performed to evaluate
extrusion appearance characteristics of electric wires.
[0273] In the extrusion appearance test 1, evaluation was made by
observing extrusion appearance at the time of manufacturing
electric wires. Specifically, when extrusion was conducted using an
extruder having a screw diameter of 25 mm at a linear velocity of
10 m/min, an electric wire having favorable appearance is taken as
"A", one having slightly poor appearance is taken as "B", and one
having significantly poor appearance is taken as "C", and "A" and
"B" are acceptable levels as products.
<Extrusion Appearance Characteristics 2 of Electric Wire>
[0274] Extrusion appearance test 2 was conducted, to evaluate
extrusion appearance characteristics of electric wires produced
under conditions in which the aggregated substance was easily
generated (in the case of melt-blending components at a higher
temperature).
[0275] In the extrusion appearance test 2, an evaluation was made
by observing appearance after performing extrusion under conditions
same with the extrusion appearance test 1 by using an electric wire
produced in a manner similar to each Example and Comparative
Example, except that melt-kneading and material discharge in the
above-mentioned step (1) were performed at 180 to 210.degree. C.
for 7 minutes at the revolution number of 60 rpm, and a step (3)
and a step (b) subsequent thereto were rapidly carried out.
[0276] In the evaluation, one having favorable appearance of the
electric wire is taken as "A", one having somewhat poor appearance
is taken as "B", and one having significantly poor appearance is
taken as "C", and "A" and "B" are acceptable levels.
<Extrusion Appearance Characteristics 3 of Electric Wire>
[0277] Extrusion appearance test 3 was conducted, to evaluate
extrusion appearance characteristics of an electric wire produced
under conditions in which the aggregated substance was easily
generated (in the case of needing time from melt-blending of
components to molding).
[0278] In the extrusion appearance test 3, an evaluation was made
by observing appearance after performing extrusion under conditions
same with the extrusion appearance test 1 by using an electric wire
produced in a manner similar to each Example and Comparative
Example, except that a heat-resistant silane crosslinkable resin
composition which was obtained by performing melt-kneading and
material discharge in the above-mentioned step (1) at 180 to
210.degree. C. for 7 minutes at the revolution number of 60 rpm and
carrying out a step (3) subsequent thereto, was left for 24 hours
under an atmosphere of 30.degree. C. and a humidity of 95%, and
then a step (b) and a step (c) were carried out.
[0279] In the evaluation, one having favorable appearance of the
electric wire is taken as "A", one having somewhat poor appearance
is taken as "B", and one having significantly poor appearance is
taken as "C", and "A" and "B" are acceptable levels.
<Heat Resistance Test 3>
[0280] With regard to Examples 38 to 40, a heat resistance test 3
was conducted in accordance with "heat deformation test" specified
in JIS C 3005. A load was adjusted to 5 N, and heating temperature
was adjusted to 160.degree. C.
[0281] In the evaluation, one having a deformation ratio of 40% or
less is taken as "A" (desirable level), and one having a ratio more
than 40% is taken as "B".
[0282] In the heat resistance test 3, the step (c) under the
above-described conditions was not carried out, and the composition
was left for 96 hours under an atmosphere of 25.degree. C. and a
humidity of 70%. This test was conducted as a reference test.
Accordingly, the results are not always required to reach the
desirable levels.
<Heat Resistance Test 4>
[0283] With regard to Examples 38 to 40, a heat resistance test 4
was conducted in accordance with "heat deformation test" specified
in JIS C 3005. A load was adjusted to 5 N, and heating temperature
was adjusted to 160.degree. C.
[0284] In the evaluation, one having a deformation ratio of 40% or
less is taken as "A" (desirable level), and one having a ratio more
than 40% is taken as "B".
[0285] In the heat resistance test 4, the step (c) under the
above-described conditions was not carried out, and the composition
was left for 24 hours under an atmosphere of 25.degree. C. and a
humidity of 70%. This test was conducted as a reference test.
Accordingly, the results are not always required to reach the
desirable levels.
TABLE-US-00001 TABLE 1 Comparative Example This invention 1 2 3 4 1
Silane Base resin Resin A UE320 95 MB (R.sub.B) Resin B SP0540 60
Resin C ENGAGE 7256 95 Resin D EV170 65 Resin E NUC6510 75 Styrene
elastomer SEPTON 4077 20 Ethylene rubber A EPT3045 25 Ethylene
rubber B EPT0045 30 Non-aromatic organic oil COSMO NEUTRAL 500 10
Content ratio (Non-aromatic organic oil:styrene elastomer) -- -- --
-- -- (Non-aromatic organic oil:ethylene rubber) -- -- -- -- 2:5
Inorganic filler Magnesium hydroxide 1 KISUMA 5 100 100 Magnesium
hydroxide 2 KISUMA 5L 100 100 Aluminum hydroxide Higilite 42M 100
Calcium carbonate SOFTON 1200 Silane coupling agent
Vinyltrimethoxysilane KBM1003 5 6.5 2 6.5 6.5 Organic peroxide
Organic peroxide Perkadox BC-FF 0.2 0.1 0.1 0.3 0.2 Catalyst
Carrier resin Resin A UE320 5 5 5 5 5 MB Silanol condensation
Silanol condensation ADKSTAB OT-1 0.1 0.1 0.1 0.1 0.1 catalyst
catalyst Evaluation Mechanical characteristics Tensile strength A A
A A A Tensile elongation A A A A A Heat resistance test 1 A A A A A
Heat resistance test 2 A A B B A Extrusion appearance
characteristics 1 of electric wire A A A A A Bleed characteristics
of electric wire A A A A A Extrusion appearance characteristics 2
of electric wire C B C B A Extrusion appearance characteristics 3
of electric wire C C C C A This invention 2 3 4 5 6 Silane Base
resin Resin A UE320 MB (R.sub.B) Resin B SP0540 60 60 60 60 60
Resin C ENGAGE 7256 Resin D EV170 Resin E NUC6510 Styrene elastomer
SEPTON 4077 Ethylene rubber A EPT3045 25 25 25 25 25 Ethylene
rubber B EPT0045 Non-aromatic organic oil COSMO NEUTRAL 500 10 10
10 10 10 Content ratio (Non-aromatic organic oil:styrene elastomer)
-- -- -- -- -- (Non-aromatic organic oil:ethylene rubber) 2:5 2:5
2:5 2:5 2:5 Inorganic filler Magnesium hydroxide 1 KISUMA 5 50 300
Magnesium hydroxide 2 KISUMA 5L 100 Aluminum hydroxide Higilite 42M
100 Calcium carbonate SOFTON 1200 100 Silane coupling agent
Vinyltrimethoxysilane KBM1003 6.5 6.5 6.5 6.5 6.5 Organic peroxide
Organic peroxide Perkadox BC-FF 0.2 0.2 0.2 0.2 0.2 Catalyst
Carrier resin Resin A UE320 5 5 5 5 5 MB Silanol condensation
Silanol condensation ADKSTAB OT-1 0.1 0.1 0.1 0.1 0.1 catalyst
catalyst Evaluation Mechanical characteristics Tensile strength A A
A A A Tensile elongation A A A A B Heat resistance test 1 A A A A A
Heat resistance test 2 A A A A A Extrusion appearance
characteristics 1 of electric wire A A A A A Bleed characteristics
of electric wire A A A A A Extrusion appearance characteristics 2
of electric wire A A A A A Extrusion appearance characteristics 3
of electric wire A A A A A Comparative This Comparative Example
invention Example 5 7 8 6 Silane Base resin Resin A UE320 MB
(R.sub.B) Resin B SP0540 60 60 60 60 Resin C ENGAGE 7256 Resin D
EV170 Resin E NUC6510 Styrene elastomer SEPTON 4077 Ethylene rubber
A EPT3045 25 25 25 25 Ethylene rubber B EPT0045 Non-aromatic
organic oil COSMO NEUTRAL 500 10 10 10 10 Content ratio
(Non-aromatic organic oil:styrene elastomer) -- -- -- --
(Non-aromatic organic oil:ethylene rubber) 2:5 2:5 2:5 2:5
Inorganic filler Magnesium hydroxide 1 KISUMA 5 100 100 100 100
Magnesium hydroxide 2 KISUMA 5L Aluminum hydroxide Higilite 42M
Calcium carbonate SOFTON 1200 Silane coupling agent
Vinyltrimethoxysilane KBM1003 6.5 6.5 6.5 6.5 Organic peroxide
Organic peroxide Perkadox BC-FF 0.005 0..05 0.4 0.9 Catalyst
Carrier resin Resin A UE320 5 5 5 5 MB Silanol condensation Silanol
condensation ADKSTAB OT-1 0.1 0.1 0.1 0.1 catalyst catalyst
Evaluation Mechanical characteristics Tensile strength A A A
Extrusion was Tensile elongation B A A impossible Heat resistance
test 1 B A A Heat resistance test 2 C B A Extrusion appearance
characteristics 1 of electric wire A A B Bleed characteristics of
electric wire A A A Extrusion appearance characteristics 2 of
electric wire A A B Extrusion appearance characteristics 3 of
electric wire A A B
TABLE-US-00002 TABLE 2 This invention 9 10 11 12 13 14 15 16 Silane
Base resin Resin A UE320 MB (R.sub.B) Resin B SP0540 70 55 45 50 70
65 60 50 Resin C ENGAGE 7256 Resin D EV170 Resin E NUC6510 Styrene
elastomer SEPTON 4077 15 15 15 38 Ethylene rubber A EPT3045 15 15
15 38 Ethylene rubber B EPT0045 Non-aromatic organic oil COSMO
NEUTRAL 500 10 25 35 7 10 15 20 7 Content ratio (Non-aromatic
organic oil:styrene elastomer) 2:3 5:3 7:3 7:38 -- -- -- --
(Non-aromatic organic oil:ethylene rubber) -- -- -- -- 2:3 1:1 4:3
7:38 Inorganic filler Magnesium hydroxide 1 KISUMA 5 100 100 100
100 100 100 100 100 Magnesium hydroxide 2 KISUMA 5L Aluminum
hydroxide Higilite 42M Calcium carbonate SOFTON 1200 Silane
coupling agent Vinyltrimethoxysilane KBM1003 6.5 6.5 6.5 6.5 6.5
6.5 6.5 6.5 Organic peroxide Organic peroxide Perkadox BC-FF 0.2
0.2 0.2 0.2 0.2 0.2 0.2 0.2 Catalyst Carrier resin Resin A UE320 5
5 5 5 5 5 5 5 MB Silanol condensation Silanol condensation ADKSTAB
OT-1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 catalyst catalyst Evaluation
Mechanical characteristics Tensile strength A A A A A A A A Tensile
elongation A A A A A A A A Heat resistance test 1 A A A A A A A A
Heat resistance test 2 A A A A A A A A Extrusion appearance
characteristics 1 of electric wire A A A A A A A A Bleed
characteristics of electric wire A A B A A A B A Extrusion
appearance characteristics 2 of electric wire A A A A A A A A
Extrusion appearance characteristics 3 of electric wire A A A B A A
A B This invention 17 18 19 20 21 22 23 24 Silane Base resin Resin
A UE320 MB (R.sub.B) Resin B SP0540 70 65 60 50 70 65 50 50 Resin C
ENGAGE 7256 Resin D EV170 Resin E NUC6510 Styrene elastomer SEPTON
4077 7.5 7.5 7.5 19 Ethylene rubber A EPT3045 7.5 7.5 7.5 19
Ethylene rubber B EPT0045 15 15 15 38 Non-aromatic organic oil
COSMO NEUTRAL 500 10 15 20 7 10 15 30 7 Content ratio (Non-aromatic
organic oil:styrene elastomer) -- -- -- -- 4:3 2:1 4:1 7:19
(Non-aromatic organic oil:ethylene rubber) 2:3 1:1 4:3 7:38 4:3 2:1
4:1 7:19 Inorganic filler Magnesium hydroxide 1 KISUMA 5 100 100
100 100 100 100 100 100 Magnesium hydroxide 2 KISUMA 5L Aluminum
hydroxide Higilite 42M Calcium carbonate SOFTON 1200 Silane
coupling agent Vinyltrimethoxysilane KBM1003 6.5 6.5 6.5 6.5 6.5
6.5 6.5 6.5 Organic peroxide Organic peroxide Perkadox BC-FF 0.2
0.2 0.2 0.2 0.2 0.2 0.2 0.2 Catalyst Carrier resin Resin A UE320 5
5 5 5 5 5 5 5 MB Silanol condensation Silanol condensation ADKSTAB
OT-1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 catalyst catalyst Evaluation
Mechanical characteristics Tensile strength A A A A A A A A Tensile
elongation A A A A A A A A Heat resistance test 1 A A A A A A A A
Heat resistance test 2 A A A A A A A A Extrusion appearance
characteristics 1 of electric wire A A A A A A A A Bleed
characteristics of electric wire A A B A A A B A Extrusion
appearance characteristics 2 of electric wire A A A A A A A A
Extrusion appearance characteristics 3 of electric wire A A A B A A
A B
TABLE-US-00003 TABLE 3 Comparative This invention Example 25 26 27
7 Silane Base resin Resin A UE320 MB (R.sub.B) Resin B SP0540 65 65
65 65 Resin C ENGAGE 7256 Resin D EV170 Resin E NUC6510 Styrene
elastomer SEPTON 4077 7.5 7.5 7.5 7.5 Ethylene rubber A EPT3045 7.5
7.5 7.5 7.5 Ethylene rubber B EPT0045 Non-aromatic organic oil
COSMO NEUTRAL 500 15 15 15 15 Content ratio (Non-aromatic organic
oil:styrene elastomer) 2:1 2:1 2:1 2:1 (Non-aromatic organic
oil:ethylene rubber) 2:1 2:1 2:1 2:1 Inorganic filler Magnesium
hydroxide 1 KISUMA 5 100 100 100 100 Magnesium hydroxide 2 KISUMA
5L Aluminum hydroxide Higilite 42M Calcium carbonate SOFTON 1200
Silane coupling agent Vinyltrimethoxysilane KBM1003 3 5 12 25
Organic peroxide Organic peroxide Perkadox BC-FF 0.2 0.2 0.2 0.2
Catalyst Carrier resin Resin A UE320 5 5 5 5 MB Silanol
condensation Silanol condensation ADKSTAB OT-1 0.1 0.1 0.1 0.1
catalyst catalyst Evaluation Mechanical characteristics Tensile
strength A A A A Tensile elongation A A A A Heat resistance test 1
A A A A Heat resistance test 2 A A A B Extrusion appearance
characteristics 1 of electric wire A A A C Bleed characteristics of
electric wire A A B B Extrusion appearance characteristics 2 of
electric wire B A A C Extrusion appearance characteristics 3 of
electric wire B B A C Comparative This invention Example 28 29 30 8
Silane Base resin Resin A UE320 MB (R.sub.B) Resin B SP0540 Resin C
ENGAGE 7256 89 85 65 45 Resin D EV170 Resin E NUC6510 Styrene
elastomer SEPTON 4077 Ethylene rubber A EPT3045 Ethylene rubber B
EPT0045 Non-aromatic organic oil COSMO NEUTRAL 500 6 10 30 50
Content ratio (Non-aromatic organic oil:styrene elastomer) -- -- --
-- (Non-aromatic organic oil:ethylene rubber) -- -- -- -- Inorganic
filler Magnesium hydroxide 1 KISUMA 5 100 100 100 100 Magnesium
hydroxide 2 KISUMA 5L Aluminum hydroxide Higilite 42M Calcium
carbonate SOFTON 1200 Silane coupling agent Vinyltrimethoxysilane
KBM1003 6.5 6.5 6.5 6.5 Organic peroxide Organic peroxide Perkadox
BC-FF 0.2 0.2 0.2 0.2 Catalyst Carrier resin Resin A UE320 5 5 5 5
MB Silanol condensation Silanol condensation ADKSTAB OT-1 0.1 0.1
0.1 0.1 catalyst catalyst Evaluation Mechanical characteristics
Tensile strength A A A B Tensile elongation A A A A Heat resistance
test 1 A A A B Heat resistance test 2 A A A C Extrusion appearance
characteristics 1 of electric wire A A A A Bleed characteristics of
electric wire C C C C Extrusion appearance characteristics 2 of
electric wire B A A A Extrusion appearance characteristics 3 of
electric wire B A A A This invention 31 32 33 34 35 36 37 Silane
Base resin Resin A UE320 55 MB (R.sub.B) Resin B SP0540 55 Resin C
ENGAGE 7256 55 20 35 Resin D EV170 55 Resin E NUC6510 55 Styrene
elastomer SEPTON 4077 45 35 Ethylene rubber A EPT3045 25 25 25 25
25 Ethylene rubber B EPT0045 Non-aromatic organic oil COSMO NEUTRAL
500 15 15 15 15 15 30 25 Content ratio (Non-aromatic organic
oil:styrene elastomer) -- -- -- -- -- 6:9 5:7 (Non-aromatic organic
oil:ethylene rubber) 3:5 3:5 3:5 3:5 3:5 -- -- Inorganic filler
Magnesium hydroxide 1 KISUMA 5 100 100 100 100 100 100 100
Magnesium hydroxide 2 KISUMA 5L Aluminum hydroxide Higilite 42M
Calcium carbonate SOFTON 1200 Silane coupling agent
Vinyltrimethoxysilane KBM1003 6.5 6.5 6.5 6.5 6.5 6.5 6.5 Organic
peroxide Organic peroxide Perkadox BC-FF 0.2 0.2 0.2 0.2 0.2 0.4
0.2 Catalyst Carrier resin Resin A UE320 5 5 5 5 5 5 5 MB Silanol
condensation Silanol condensation ADKSTAB OT-1 0.1 0.1 0.1 0.1 0.1
0.1 0.1 catalyst catalyst Evaluation Mechanical characteristics
Tensile strength A A A A A A A Tensile elongation A A A A A A A
Heat resistance test 1 A A A A A A A Heat resistance test 2 B A A B
B B A Extrusion appearance characteristics 1 of electric wire A A A
A A B A Bleed characteristics of electric wire A A A A A A A
Extrusion appearance characteristics 2 of electric wire A A A A A B
A Extrusion appearance characteristics 3 of electric wire A A A A A
B A
TABLE-US-00004 TABLE 4 This invention 38 39 40 41 42 43 Silane Base
resin Resin A UE320 MB (R.sub.B) Resin B SP0540 60 60 60 60 60 60
Resin C ENGAGE 7256 Resin D EV170 Resin E NUC6510 Styrene elastomer
SEPTON 4077 Ethylene rubber A EPT3045 25 25 25 25 25 25 Ethylene
rubber B EPT0045 Non-aromatic organic oil COSMO NEUTRAL 500 10 10
10 10 10 10 Content ratio (Non-aromatic organic oil:styrene
elastomer) -- -- -- -- -- -- (Non-aromatic organic oil:ethylene
rubber) 2:5 2:5 2:5 2:5 2:5 2:5 Inorganic filler Magnesium
hydroxide 1 KISUMA 5 100 100 100 100 100 100 Magnesium hydroxide 2
KISUMA 5L Aluminum hydroxide Higilite 42M Calcium carbonate SOFTON
1200 Silane coupling agent Vinyltrimethoxysilane KBM1003 6.5 6.5
6.5 6.5 6.5 6.5 Organic peroxide Organic peroxide Perkadox BC-FF
0.2 0.2 0.2 0.2 0.2 0.2 Catalyst Carrier resin Resin A UE320 5 5 5
5 5 5 MB Silanol condensation Silanol condensation ADKSTAB OT-1
0.05 0.13 0.4 0.1 0.1 0.1 catalyst catalyst Evaluation Mechanical
characteristics Tensile strength A A A A A A Tensile elongation A A
A A A A Heat resistance test 1 A A A A A A Heat resistance test 2 A
A A A A A Extrusion appearance characteristics 1 of electric wire A
A A A A A Bleed characteristics of electric wire A A A A A A
Extrusion appearance characteristics 2 of electric wire A A B A A A
Extrusion appearance characteristics 3 of electric wire A A B A A A
Heat resistance test 3 A A A Heat resistance test 4 B A A
[0286] As is clear from the results in Table 1 to Table 4, in all
of Examples 1 to 43, the electric wires passed the extrusion
appearance characteristics 2 and the extrusion appearance
characteristics 3, and it was possible to produce electric wires
having excellent appearance even under conditions in which the
aggregated substance was easily generated. In addition, in all of
Examples 1 to 43, it was possible to produce electric wires that
also passed the mechanical characteristics and the heat
resistance.
[0287] Further, as is clear from the results in Table 4, even when
no warm water treatment or the like was applied in the step (c),
and the content of the silanol condensation catalyst was changed to
0.05 to 0.4 parts by mass with respect to 100 parts by mass of the
base resin (R.sub.B), the electric wires that passed each test of
the appearance, the mechanical characteristics, and the heat
resistance, and also the heat resistant test 3, and further the
heat resistant test 4, and had excellent heat resistance were able
to be produced.
[0288] Thus, the heat-resistant silane crosslinked resin molded
bodies provided as the coatings of the electric wires in Examples 1
to 43 in the present invention had the excellent appearance even
when the molded bodies were produced under the conditions in which
the aggregated substance was easily generated. Furthermore, the
molded bodies were excellent also in the mechanical characteristics
and the heat resistance. It can be easily understood that the flame
retardancy is excellent from the mixing amount of the inorganic
filler.
[0289] In contrast, in all of Comparative Examples 1 to 4 in which
the base resin (R.sub.B) containing no non-aromatic organic oil was
used, the electric wires failed in the extrusion appearance
characteristics 2 and the extrusion appearance characteristics 3,
although the electric wires passed the extrusion appearance test 1.
On the other hand, in Comparative Example 8 in which the content of
the non-aromatic organic oil was high, the electric wire failed in
the heat resistance tests 1 and 2.
[0290] In addition, in Comparative Example 5 in which the ratio of
using the organic peroxide was low, the electric wire failed in the
heat resistance tests 1 and 2, and in Comparative Example 6 in
which the ratio of using the organic peroxide was high, even
extrusion molding was unable to be made.
[0291] Further, in Comparative Example 7 in which the content of
the silane coupling agent was high, the electric wire did not pass
even the extrusion appearance test 1, and failed also in the hot
set test 1, and also had poor heat resistance.
[0292] Having described our invention as related to the present
embodiments, it is our intention that the invention not be limited
by any of the details of the description, unless otherwise
specified, but rather be construed broadly within its spirit and
scope as set out in the accompanying claims.
* * * * *